Backport fixes and improvements from external Keras.

Change: 152198296

22 files changed, 424 insertions, 150 deletions

diff --git a/tensorflow/contrib/keras/python/keras/__init__.py b/tensorflow/contrib/keras/python/keras/__init__.py
index cdfc40dff1..ec316253db 100644
--- a/tensorflow/contrib/keras/python/keras/__init__.py
+++ b/tensorflow/contrib/keras/python/keras/__init__.py
@@ -37,4 +37,4 @@ from tensorflow.contrib.keras.python.keras import utils
 from tensorflow.contrib.keras.python.keras import wrappers
 
 
-__version__ = '2.0.0-tf'
+__version__ = '2.0.2-tf'
diff --git a/tensorflow/contrib/keras/python/keras/activations.py b/tensorflow/contrib/keras/python/keras/activations.py
index 1eac52dfad..67762c83ba 100644
--- a/tensorflow/contrib/keras/python/keras/activations.py
+++ b/tensorflow/contrib/keras/python/keras/activations.py
@@ -24,18 +24,28 @@ from tensorflow.contrib.keras.python.keras import backend as K
 from tensorflow.contrib.keras.python.keras.utils.generic_utils import deserialize_keras_object
 
 
-def softmax(x):
+def softmax(x, axis=-1):
+  """Softmax activation function.
+
+  Arguments:
+      x : Tensor.
+      axis: Integer, axis along which the softmax normalization is applied.
+
+  Returns:
+      Tensor, output of softmax transformation.
+
+  Raises:
+      ValueError: In case `dim(x) == 1`.
+  """
   ndim = K.ndim(x)
   if ndim == 2:
     return K.softmax(x)
-  elif ndim == 3:
-    e = K.exp(x - K.max(x, axis=-1, keepdims=True))
-    s = K.sum(e, axis=-1, keepdims=True)
+  elif ndim > 2:
+    e = K.exp(x - K.max(x, axis=axis, keepdims=True))
+    s = K.sum(e, axis=axis, keepdims=True)
     return e / s
   else:
-    raise ValueError('Cannot apply softmax to a tensor '
-                     'that is not 2D or 3D. '
-                     'Here, ndim=' + str(ndim))
+    raise ValueError('Cannot apply softmax to a tensor that is 1D')
 
 
 def elu(x, alpha=1.0):
diff --git a/tensorflow/contrib/keras/python/keras/applications/resnet50.py b/tensorflow/contrib/keras/python/keras/applications/resnet50.py
index 546fcb9433..12f7ca424e 100644
--- a/tensorflow/contrib/keras/python/keras/applications/resnet50.py
+++ b/tensorflow/contrib/keras/python/keras/applications/resnet50.py
@@ -163,8 +163,8 @@ def ResNet50(include_top=True,
   specified in your Keras config file.
 
   Arguments:
-      include_top: whether to include the 3 fully-connected
-          layers at the top of the network.
+      include_top: whether to include the fully-connected
+          layer at the top of the network.
       weights: one of `None` (random initialization)
           or "imagenet" (pre-training on ImageNet).
       input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
diff --git a/tensorflow/contrib/keras/python/keras/backend.py b/tensorflow/contrib/keras/python/keras/backend.py
index 9769bce3b0..d7c646c19a 100644
--- a/tensorflow/contrib/keras/python/keras/backend.py
+++ b/tensorflow/contrib/keras/python/keras/backend.py
@@ -22,7 +22,6 @@ from __future__ import division
 from __future__ import print_function
 
 from collections import defaultdict
-import errno
 import json
 import os
 import warnings
@@ -270,6 +269,7 @@ def clear_session():
   reset_uids()
   _SESSION = None
   phase = array_ops.placeholder(dtype='bool', name='keras_learning_phase')
+  _GRAPH_LEARNING_PHASES = {}
   _GRAPH_LEARNING_PHASES[ops.get_default_graph()] = phase
 
 
@@ -1257,6 +1257,34 @@ def prod(x, axis=None, keepdims=False):
   return math_ops.reduce_prod(x, reduction_indices=axis, keep_dims=keepdims)
 
 
+def cumsum(x, axis=0):
+  """Cumulative sum of the values in a tensor, alongside the specified axis.
+
+  Arguments:
+      x: A tensor or variable.
+      axis: An integer, the axis to compute the sum.
+
+  Returns:
+      A tensor of the cumulative sum of values of `x` along `axis`.
+  """
+  axis = _normalize_axis(axis, ndim(x))
+  return math_ops.cumsum(x, axis=axis)
+
+
+def cumprod(x, axis=0):
+  """Cumulative product of the values in a tensor, alongside the specified axis.
+
+  Arguments:
+      x: A tensor or variable.
+      axis: An integer, the axis to compute the product.
+
+  Returns:
+      A tensor of the cumulative product of values of `x` along `axis`.
+  """
+  axis = _normalize_axis(axis, ndim(x))
+  return math_ops.cumprod(x, axis=axis)
+
+
 def var(x, axis=None, keepdims=False):
   """Variance of a tensor, alongside the specified axis.
 
@@ -1330,8 +1358,7 @@ def any(x, axis=None, keepdims=False):
   """
   axis = _normalize_axis(axis, ndim(x))
   x = math_ops.cast(x, dtypes_module.bool)
-  x = math_ops.reduce_any(x, reduction_indices=axis, keep_dims=keepdims)
-  return math_ops.cast(x, dtypes_module.uint8)
+  return math_ops.reduce_any(x, reduction_indices=axis, keep_dims=keepdims)
 
 
 def all(x, axis=None, keepdims=False):
@@ -1347,8 +1374,7 @@ def all(x, axis=None, keepdims=False):
   """
   axis = _normalize_axis(axis, ndim(x))
   x = math_ops.cast(x, dtypes_module.bool)
-  x = math_ops.reduce_all(x, reduction_indices=axis, keep_dims=keepdims)
-  return math_ops.cast(x, dtypes_module.uint8)
+  return math_ops.reduce_all(x, reduction_indices=axis, keep_dims=keepdims)
 
 
 def argmax(x, axis=-1):
@@ -1645,7 +1671,7 @@ def normalize_batch_in_training(x, gamma, beta, reduction_axes, epsilon=1e-3):
   """
   mean, var = nn.moments(
       x, reduction_axes, shift=None, name=None, keep_dims=False)
-  if sorted(reduction_axes) == range(ndim(x))[:-1]:
+  if sorted(reduction_axes) == list(range(ndim(x)))[:-1]:
     normed = nn.batch_normalization(x, mean, var, beta, gamma, epsilon)
   else:
     # need broadcasting
@@ -2324,8 +2350,8 @@ def rnn(step_function,
           (no time dimension),
           containing the initial values for the states used in
           the step function.
-      go_backwards: boolean. If True, do the iteration over
-          the time dimension in reverse order.
+      go_backwards: boolean. If True, do the iteration over the time
+          dimension in reverse order and return the reversed sequence.
       mask: binary tensor with shape `(samples, time, 1)`,
           with a zero for every element that is masked.
       constants: a list of constant values passed at each step.
@@ -2414,9 +2440,9 @@ def rnn(step_function,
         states = return_states
         successive_outputs.append(output)
         successive_states.append(states)
-        last_output = successive_outputs[-1]
-        new_states = successive_states[-1]
-        outputs = array_ops.stack(successive_outputs)
+      last_output = successive_outputs[-1]
+      new_states = successive_states[-1]
+      outputs = array_ops.stack(successive_outputs)
     else:
       for inp in input_list:
         output, states = step_function(inp, states + constants)
@@ -3534,19 +3560,19 @@ def ctc_decode(y_pred, input_length, greedy=True, beam_width=100, top_paths=1):
 # HIGH ORDER FUNCTIONS
 
 
-def map_fn(fn, elems, name=None):
+def map_fn(fn, elems, name=None, dtype=None):
   """Map the function fn over the elements elems and return the outputs.
 
   Arguments:
       fn: Callable that will be called upon each element in elems
       elems: tensor
       name: A string name for the map node in the graph
+      dtype: Output data type.
 
   Returns:
-      Tensor with first dimension equal to the elems and second depending on
-      fn
+      Tensor with dtype `dtype`.
   """
-  return functional_ops.map_fn(fn, elems, name=name)
+  return functional_ops.map_fn(fn, elems, name=name, dtype=dtype)
 
 
 def foldl(fn, elems, initializer=None, name=None):
@@ -3560,7 +3586,7 @@ def foldl(fn, elems, initializer=None, name=None):
       name: A string name for the foldl node in the graph
 
   Returns:
-      Same type and shape as initializer
+      Tensor with same type and shape as `initializer`.
   """
   return functional_ops.foldl(fn, elems, initializer=initializer, name=name)
 
@@ -3583,27 +3609,39 @@ def foldr(fn, elems, initializer=None, name=None):
 
 # Load Keras default configuration from config file if present.
 _keras_base_dir = os.path.expanduser('~')
-if not os.access(_keras_base_dir, os.W_OK):
-  _keras_base_dir = '/tmp'
 _keras_dir = os.path.join(_keras_base_dir, '.keras')
-if not os.path.exists(_keras_dir):
-  try:
-    os.makedirs(_keras_dir)
-  except OSError as e:
-    if e.errno == errno.EEXIST:
-      pass
-    else:
-      raise
 _config_path = os.path.expanduser(os.path.join(_keras_dir, 'keras.json'))
 if os.path.exists(_config_path):
-  _config = json.load(open(_config_path))
+  try:
+    _config = json.load(open(_config_path))
+  except json.decoder.JSONDecodeError:
+    _config = {}
   _floatx = _config.get('floatx', floatx())
   assert _floatx in {'float16', 'float32', 'float64'}
   _epsilon = _config.get('epsilon', epsilon())
   assert isinstance(_epsilon, float)
-  _backend = backend()
   _image_data_format = _config.get('image_data_format', image_data_format())
   assert _image_data_format in {'channels_last', 'channels_first'}
   set_floatx(_floatx)
   set_epsilon(_epsilon)
   set_image_data_format(_image_data_format)
+
+# Save config file.
+if os.access(_keras_base_dir, os.W_OK):
+  if not os.path.exists(_keras_dir):
+    try:
+      os.makedirs(_keras_dir)
+    except OSError:
+      # Except potential race conditions
+      # in multi-threaded environments.
+      pass
+
+  if not os.path.exists(_config_path):
+    _config = {
+        'floatx': floatx(),
+        'epsilon': epsilon(),
+        'backend': 'tensorflow',
+        'image_data_format': image_data_format()
+    }
+    with open(_config_path, 'w') as f:
+      f.write(json.dumps(_config, indent=4))
diff --git a/tensorflow/contrib/keras/python/keras/engine/topology.py b/tensorflow/contrib/keras/python/keras/engine/topology.py
index 0f506ff0a4..e33268235f 100644
--- a/tensorflow/contrib/keras/python/keras/engine/topology.py
+++ b/tensorflow/contrib/keras/python/keras/engine/topology.py
@@ -295,8 +295,14 @@ class Layer(object):
     # are only applicable to input layers: do not pass these keywords
     # to non-input layers.
     allowed_kwargs = {
-        'input_shape', 'batch_input_shape', 'batch_size', 'dtype', 'name',
-        'trainable', 'weights'
+        'input_shape',
+        'batch_input_shape',
+        'batch_size',
+        'dtype',
+        'name',
+        'trainable',
+        'weights',
+        'input_dtype',  # legacy
     }
     for kwarg in kwargs:
       if kwarg not in allowed_kwargs:
@@ -320,8 +326,15 @@ class Layer(object):
           batch_size = None
         batch_input_shape = (batch_size,) + tuple(kwargs['input_shape'])
       self.batch_input_shape = batch_input_shape
-      dtype = kwargs.get('dtype', K.floatx())
+
+      # Set dtype.
+      dtype = kwargs.get('dtype')
+      if dtype is None:
+        dtype = kwargs.get('input_dtype')
+      if dtype is None:
+        dtype = K.floatx()
       self.dtype = dtype
+
     if 'weights' in kwargs:
       self._initial_weights = kwargs['weights']
     else:
@@ -485,11 +498,12 @@ class Layer(object):
                                  ': expected shape=' + str(spec.shape) +
                                  ', found shape=' + str(x_shape))
 
-  def call(self, inputs):
+  def call(self, inputs, **kwargs):  # pylint: disable=unused-argument
     """This is where the layer's logic lives.
 
     Arguments:
-        inputs: input tensor, or list/tuple of input tensors.
+        inputs: Input tensor, or list/tuple of input tensors.
+        **kwargs: Additional keyword arguments.
 
     Returns:
         A tensor or list/tuple of tensors.
@@ -518,6 +532,8 @@ class Layer(object):
         ValueError: in case the layer is missing shape information
             for its `build` call.
     """
+    if isinstance(inputs, list):
+      inputs = inputs[:]
     with K.name_scope(self.name):
       # Handle laying building (weight creating, input spec locking).
       if not self.built:
@@ -1417,7 +1433,7 @@ class Container(Layer):
       get_weights
       set_weights
       get_config
-      get_output_shape_for
+      compute_output_shape
 
   # Class Methods
       from_config
@@ -2029,7 +2045,7 @@ class Container(Layer):
       for i in range(len(input_shapes)):
         layer = self.input_layers[i]
         input_shape = input_shapes[i]
-        # It's an input layer: get_output_shape_for is identity,
+        # It's an input layer: compute_output_shape is identity,
         # and there is only one node and one tensor output.
         shape_key = layer.name + '_0_0'
         layers_to_output_shapes[shape_key] = input_shape
diff --git a/tensorflow/contrib/keras/python/keras/engine/training.py b/tensorflow/contrib/keras/python/keras/engine/training.py
index efd437f6f6..0097c4a1c2 100644
--- a/tensorflow/contrib/keras/python/keras/engine/training.py
+++ b/tensorflow/contrib/keras/python/keras/engine/training.py
@@ -733,11 +733,12 @@ class Model(Container):
       loss_functions = []
       for name in self.output_names:
         if name not in loss:
-          warnings.warn('Output "' + name + '" missing from loss dictionary. '
-                        'We assume this was done on purpose, '
-                        'and we will not be expecting '
-                        'any data to be passed to "' + name +
-                        '" during training.')
+          warnings.warn(
+              'Output "' + name + '" missing from loss dictionary. '
+              'We assume this was done on purpose, '
+              'and we will not be expecting '
+              'any data to be passed to "' + name + '" during training.',
+              stacklevel=2)
         loss_functions.append(losses.get(loss.get(name)))
     elif isinstance(loss, list):
       if len(loss) != len(self.outputs):
@@ -1202,7 +1203,7 @@ class Model(Container):
       if batch_index == 0:
         for batch_out in batch_outs:
           shape = (samples,) + batch_out.shape[1:]
-          outs.append(np.zeros(shape, dtype=K.floatx()))
+          outs.append(np.zeros(shape, dtype=batch_out.dtype))
 
       for i, batch_out in enumerate(batch_outs):
         outs[i][batch_start:batch_end] = batch_out
@@ -1718,7 +1719,7 @@ class Model(Container):
             - a tuple (inputs, targets, sample_weights).
             All arrays should contain the same number of samples.
             The generator is expected to loop over its data
-            indefinitely. An epoch finishes when `samples_per_epoch`
+            indefinitely. An epoch finishes when `steps_per_epoch`
             samples have been seen by the model.
         steps_per_epoch: Total number of steps (batches of samples)
             to yield from `generator` before declaring one epoch
@@ -1767,7 +1768,7 @@ class Model(Container):
                 f.close()
 
         model.fit_generator(generate_arrays_from_file('/my_file.txt'),
-                            samples_per_epoch=10000, epochs=10)
+                            steps_per_epoch=10000, epochs=10)
     ```
 
     Raises:
@@ -2028,7 +2029,8 @@ class Model(Container):
                         steps,
                         max_q_size=10,
                         workers=1,
-                        pickle_safe=False):
+                        pickle_safe=False,
+                        verbose=0):
     """Generates predictions for the input samples from a data generator.
 
     The generator should return the same kind of data as accepted by
@@ -2048,6 +2050,7 @@ class Model(Container):
             non picklable arguments to the generator
             as they can't be passed
             easily to children processes.
+        verbose: verbosity mode, 0 or 1.
 
     Returns:
         Numpy array(s) of predictions.
@@ -2067,6 +2070,9 @@ class Model(Container):
       enqueuer = GeneratorEnqueuer(generator, pickle_safe=pickle_safe)
       enqueuer.start(workers=workers, max_q_size=max_q_size)
 
+      if verbose == 1:
+        progbar = Progbar(target=steps)
+
       while steps_done < steps:
         generator_output = None
         while enqueuer.is_running():
@@ -2103,6 +2109,8 @@ class Model(Container):
         for i, out in enumerate(outs):
           all_outs[i].append(out)
         steps_done += 1
+        if verbose == 1:
+          progbar.update(steps_done)
 
     finally:
       if enqueuer is not None:
diff --git a/tensorflow/contrib/keras/python/keras/initializers.py b/tensorflow/contrib/keras/python/keras/initializers.py
index 621069f424..f9cb35e171 100644
--- a/tensorflow/contrib/keras/python/keras/initializers.py
+++ b/tensorflow/contrib/keras/python/keras/initializers.py
@@ -45,14 +45,16 @@ class Initializer(object):
 
 
 class Zeros(Initializer):
-  """Initializer that generates tensors initialized to 0."""
+  """Initializer that generates tensors initialized to 0.
+  """
 
   def __call__(self, shape, dtype=None):
     return K.constant(0, shape=shape, dtype=dtype)
 
 
 class Ones(Initializer):
-  """Initializer that generates tensors initialized to 1."""
+  """Initializer that generates tensors initialized to 1.
+  """
 
   def __call__(self, shape, dtype=None):
     return K.constant(1, shape=shape, dtype=dtype)
@@ -130,7 +132,7 @@ class RandomUniform(Initializer):
 class TruncatedNormal(Initializer):
   """Initializer that generates a truncated normal distribution.
 
-  These values are similar to values from a `random_normal_initializer`
+  These values are similar to values from a `RandomNormal`
   except that values more than two standard deviations from the mean
   are discarded and re-drawn. This is the recommended initializer for
   neural network weights and filters.
@@ -161,6 +163,7 @@ class VarianceScaling(Initializer):
 
   With `distribution="normal"`, samples are drawn from a truncated normal
   distribution centered on zero, with `stddev = sqrt(scale / n)` where n is:
+
       - number of input units in the weight tensor, if mode = "fan_in"
       - number of output units, if mode = "fan_out"
       - average of the numbers of input and output units, if mode = "fan_avg"
diff --git a/tensorflow/contrib/keras/python/keras/layers/convolutional.py b/tensorflow/contrib/keras/python/keras/layers/convolutional.py
index 1a28399a28..3b68022115 100644
--- a/tensorflow/contrib/keras/python/keras/layers/convolutional.py
+++ b/tensorflow/contrib/keras/python/keras/layers/convolutional.py
@@ -244,7 +244,7 @@ class _Conv(Layer):
         'kernel_initializer':
             initializers.serialize(self.kernel_initializer),
         'bias_initializer':
-            initializers.serialize(self.kernel_initializer),
+            initializers.serialize(self.bias_initializer),
         'kernel_regularizer':
             regularizers.serialize(self.kernel_regularizer),
         'bias_regularizer':
@@ -289,7 +289,7 @@ class Conv1D(_Conv):
           any `dilation_rate` value != 1.
       padding: One of `"valid"`, `"causal"` or `"same"` (case-insensitive).
           `"causal"` results in causal (dilated) convolutions, e.g. output[t]
-          depends solely on input[:t-1]. Useful when modeling temporal data
+          does not depend on input[t+1:]. Useful when modeling temporal data
           where the model should not violate the temporal order.
           See [WaveNet: A Generative Model for Raw Audio, section
             2.1](https://arxiv.org/abs/1609.03499).
@@ -395,9 +395,9 @@ class Conv2D(_Conv):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
@@ -621,7 +621,7 @@ class Conv2DTranspose(Conv2D):
 
   Arguments:
       filters: Integer, the dimensionality of the output space
-          (i.e. the number output of filters in the convolution).
+          (i.e. the number of output filters in the convolution).
       kernel_size: An integer or tuple/list of 2 integers, specifying the
           width and height of the 2D convolution window.
           Can be a single integer to specify the same value for
@@ -637,9 +637,9 @@ class Conv2DTranspose(Conv2D):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
@@ -688,7 +688,7 @@ class Conv2DTranspose(Conv2D):
                kernel_size,
                strides=(1, 1),
                padding='valid',
-               data_format='channels_last',
+               data_format=None,
                activation=None,
                use_bias=True,
                kernel_initializer='glorot_uniform',
@@ -845,9 +845,9 @@ class SeparableConv2D(Conv2D):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
@@ -1079,9 +1079,9 @@ class UpSampling2D(Layer):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
@@ -1257,7 +1257,7 @@ class ZeroPadding2D(Layer):
           - If tuple of 2 ints:
               interpreted as two different
               symmetric padding values for height and width:
-              `(symmetric_height_pad, symmetrc_width_pad)`.
+              `(symmetric_height_pad, symmetric_width_pad)`.
           - If tuple of 2 tuples of 2 ints:
               interpreted as
               `((top_pad, bottom_pad), (left_pad, right_pad))`
@@ -1265,9 +1265,9 @@ class ZeroPadding2D(Layer):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
@@ -1498,7 +1498,7 @@ class Cropping2D(Layer):
           - If tuple of 2 ints:
               interpreted as two different
               symmetric cropping values for height and width:
-              `(symmetric_height_crop, symmetrc_width_crop)`.
+              `(symmetric_height_crop, symmetric_width_crop)`.
           - If tuple of 2 tuples of 2 ints:
               interpreted as
               `((top_crop, bottom_crop), (left_crop, right_crop))`
@@ -1506,9 +1506,9 @@ class Cropping2D(Layer):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
diff --git a/tensorflow/contrib/keras/python/keras/layers/convolutional_recurrent.py b/tensorflow/contrib/keras/python/keras/layers/convolutional_recurrent.py
index 4ed5046dc3..4d8ef44da7 100644
--- a/tensorflow/contrib/keras/python/keras/layers/convolutional_recurrent.py
+++ b/tensorflow/contrib/keras/python/keras/layers/convolutional_recurrent.py
@@ -357,7 +357,7 @@ class ConvLSTM2D(ConvRecurrent2D):
       self.states = [None, None]
 
     if self.data_format == 'channels_first':
-      channel_axis = 1
+      channel_axis = 2
     else:
       channel_axis = -1
     if input_shape[channel_axis] is None:
diff --git a/tensorflow/contrib/keras/python/keras/layers/core.py b/tensorflow/contrib/keras/python/keras/layers/core.py
index 1207cc119f..8dd55aaa2e 100644
--- a/tensorflow/contrib/keras/python/keras/layers/core.py
+++ b/tensorflow/contrib/keras/python/keras/layers/core.py
@@ -88,7 +88,7 @@ class Dropout(Layer):
   """Applies Dropout to the input.
 
   Dropout consists in randomly setting
-  a fraction `p` of input units to 0 at each update during training time,
+  a fraction `rate` of input units to 0 at each update during training time,
   which helps prevent overfitting.
 
   Arguments:
@@ -140,7 +140,7 @@ class SpatialDropout1D(Dropout):
   between feature maps and should be used instead.
 
   Arguments:
-      p: float between 0 and 1. Fraction of the input units to drop.
+      rate: float between 0 and 1. Fraction of the input units to drop.
 
   Input shape:
       3D tensor with shape:
@@ -775,7 +775,7 @@ class Dense(Layer):
         'kernel_initializer':
             initializers.serialize(self.kernel_initializer),
         'bias_initializer':
-            initializers.serialize(self.kernel_initializer),
+            initializers.serialize(self.bias_initializer),
         'kernel_regularizer':
             regularizers.serialize(self.kernel_regularizer),
         'bias_regularizer':
diff --git a/tensorflow/contrib/keras/python/keras/layers/local.py b/tensorflow/contrib/keras/python/keras/layers/local.py
index 3bf5ee4f0f..895d6e3727 100644
--- a/tensorflow/contrib/keras/python/keras/layers/local.py
+++ b/tensorflow/contrib/keras/python/keras/layers/local.py
@@ -59,7 +59,8 @@ class LocallyConnected1D(Layer):
           specifying the stride length of the convolution.
           Specifying any stride value != 1 is incompatible with specifying
           any `dilation_rate` value != 1.
-      padding: One of `"valid"` or `"same"` (case-insensitive).
+      padding: Currently only supports `"valid"` (case-insensitive).
+          `"same"` may be supported in the future.
       activation: Activation function to use.
           If you don't specify anything, no activation is applied
           (ie. "linear" activation: `a(x) = x`).
@@ -188,7 +189,7 @@ class LocallyConnected1D(Layer):
         'kernel_initializer':
             initializers.serialize(self.kernel_initializer),
         'bias_initializer':
-            initializers.serialize(self.kernel_initializer),
+            initializers.serialize(self.bias_initializer),
         'kernel_regularizer':
             regularizers.serialize(self.kernel_regularizer),
         'bias_regularizer':
@@ -239,16 +240,15 @@ class LocallyConnected2D(Layer):
           specifying the strides of the convolution along the width and height.
           Can be a single integer to specify the same value for
           all spatial dimensions.
-          Specifying any stride value != 1 is incompatible with specifying
-          any `dilation_rate` value != 1.
-      padding: one of `"valid"` or `"same"` (case-insensitive).
+      padding: Currently only support `"valid"` (case-insensitive).
+          `"same"` will be supported in future.
       data_format: A string,
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
@@ -460,7 +460,7 @@ class LocallyConnected2D(Layer):
         'kernel_initializer':
             initializers.serialize(self.kernel_initializer),
         'bias_initializer':
-            initializers.serialize(self.kernel_initializer),
+            initializers.serialize(self.bias_initializer),
         'kernel_regularizer':
             regularizers.serialize(self.kernel_regularizer),
         'bias_regularizer':
diff --git a/tensorflow/contrib/keras/python/keras/layers/merge.py b/tensorflow/contrib/keras/python/keras/layers/merge.py
index eea4313d31..d52bd2bbb3 100644
--- a/tensorflow/contrib/keras/python/keras/layers/merge.py
+++ b/tensorflow/contrib/keras/python/keras/layers/merge.py
@@ -41,6 +41,44 @@ class _Merge(Layer):
   def _merge_function(self, inputs):
     raise NotImplementedError
 
+  def _compute_elemwise_op_output_shape(self, shape1, shape2):
+    """Computes the shape of the resultant of an elementwise operation.
+
+    Arguments:
+        shape1: tuple or None. Shape of the first tensor
+        shape2: tuple or None. Shape of the second tensor
+
+    Returns:
+        expected output shape when an element-wise operation is
+        carried out on 2 tensors with shapes shape1 and shape2.
+        tuple or None.
+
+    Raises:
+        ValueError: if shape1 and shape2 are not compatible for
+            element-wise operations.
+    """
+    if None in [shape1, shape2]:
+      return None
+    elif len(shape1) < len(shape2):
+      return self._compute_elemwise_op_output_shape(shape2, shape1)
+    elif not shape2:
+      return shape1
+    output_shape = list(shape1[:-len(shape2)])
+    for i, j in zip(shape1[-len(shape2):], shape2):
+      if i is None or j is None:
+        output_shape.append(None)
+      elif i == 1:
+        output_shape.append(j)
+      elif j == 1:
+        output_shape.append(i)
+      else:
+        if i != j:
+          raise ValueError('Operands could not be broadcast '
+                           'together with shapes ' + str(shape1) + ' ' + str(
+                               shape2))
+        output_shape.append(i)
+    return tuple(output_shape)
+
   def build(self, input_shape):
     # Used purely for shape validation.
     if not isinstance(input_shape, list):
@@ -49,23 +87,107 @@ class _Merge(Layer):
       raise ValueError('A merge layer should be called '
                        'on a list of at least 2 inputs. '
                        'Got ' + str(len(input_shape)) + ' inputs.')
-    if all([shape is None for shape in input_shape]):
-      return
-    input_shapes = [
-        tuple(tensor_shape.TensorShape(shape).as_list())
-        for shape in input_shape
-    ]
-    # TODO(fchollet): handle shapes with None entries.
-    input_shapes_set = set(input_shapes)
-    if None in input_shapes_set:
-      input_shapes_set.remove(None)
-    if len(input_shapes_set) > 1:
-      raise ValueError('Only tensors of same shape can '
-                       'be merged by layer' + self.name +
-                       ' Got input shapes: %s' % input_shapes)
+    batch_sizes = [s[0] for s in input_shape if s is not None]
+    batch_sizes = set(batch_sizes)
+    batch_sizes -= set([None])
+    if len(batch_sizes) > 1:
+      raise ValueError('Can not merge tensors with different '
+                       'batch sizes. Got tensors with shapes : ' + str(
+                           input_shape))
+    if input_shape[0] is None:
+      output_shape = None
+    else:
+      output_shape = input_shape[0][1:]
+    for i in range(1, len(input_shape)):
+      if input_shape[i] is None:
+        shape = None
+      else:
+        shape = input_shape[i][1:]
+      output_shape = self._compute_elemwise_op_output_shape(output_shape, shape)
+    # If the inputs have different ranks, we have to reshape them
+    # to make them broadcastable.
+    if None not in input_shape and len(set(map(len, input_shape))) == 1:
+      self._reshape_required = False
+    else:
+      self._reshape_required = True
 
   def call(self, inputs):
-    return self._merge_function(inputs)
+    if self._reshape_required:
+      reshaped_inputs = []
+      input_ndims = list(map(K.ndim, inputs))
+      if None not in input_ndims:
+        # If ranks of all inputs are available,
+        # we simply expand each of them at axis=1
+        # until all of them have the same rank.
+        max_ndim = max(input_ndims)
+        for x in inputs:
+          x_ndim = K.ndim(x)
+          for _ in range(max_ndim - x_ndim):
+            x = K.expand_dims(x, 1)
+          reshaped_inputs.append(x)
+        return self._merge_function(reshaped_inputs)
+      else:
+        # Transpose all inputs so that batch size is the last dimension.
+        # (batch_size, dim1, dim2, ... ) -> (dim1, dim2, ... , batch_size)
+        transposed = False
+        for x in inputs:
+          x_ndim = K.ndim(x)
+          if x_ndim is None:
+            x_shape = K.shape(x)
+            batch_size = x_shape[0]
+            new_shape = K.concatenate([x_shape[1:], K.expand_dims(batch_size)])
+            x_transposed = K.reshape(x,
+                                     K.stack([batch_size, K.prod(x_shape[1:])]))
+            x_transposed = K.permute_dimensions(x_transposed, (1, 0))
+            x_transposed = K.reshape(x_transposed, new_shape)
+            reshaped_inputs.append(x_transposed)
+            transposed = True
+          elif x_ndim > 1:
+            dims = list(range(1, x_ndim)) + [0]
+            reshaped_inputs.append(K.permute_dimensions(x, dims))
+            transposed = True
+          else:
+            # We don't transpose inputs if they are 1D vectors or scalars.
+            reshaped_inputs.append(x)
+        y = self._merge_function(reshaped_inputs)
+        y_ndim = K.ndim(y)
+        if transposed:
+          # If inputs have been transposed, we have to transpose the output too.
+          if y_ndim is None:
+            y_shape = K.shape(y)
+            y_ndim = K.shape(y_shape)[0]
+            batch_size = y_shape[y_ndim - 1]
+            new_shape = K.concatenate(
+                [K.expand_dims(batch_size), y_shape[:y_ndim - 1]])
+            y = K.reshape(y, (-1, batch_size))
+            y = K.permute_dimensions(y, (1, 0))
+            y = K.reshape(y, new_shape)
+          elif y_ndim > 1:
+            dims = [y_ndim - 1] + list(range(y_ndim - 1))
+            y = K.permute_dimensions(y, dims)
+        return y
+    else:
+      return self._merge_function(inputs)
+
+  def compute_output_shape(self, input_shape):
+    if input_shape[0] is None:
+      output_shape = None
+    else:
+      output_shape = input_shape[0][1:]
+    for i in range(1, len(input_shape)):
+      if input_shape[i] is None:
+        shape = None
+      else:
+        shape = input_shape[i][1:]
+      output_shape = self._compute_elemwise_op_output_shape(output_shape, shape)
+    batch_sizes = [s[0] for s in input_shape if s is not None]
+    batch_sizes = set(batch_sizes)
+    batch_sizes -= set([None])
+    if len(batch_sizes) == 1:
+      output_shape = (list(batch_sizes)[0],) + output_shape
+    else:
+      output_shape = (None,) + output_shape
+    return output_shape
 
   def compute_mask(self, inputs, mask=None):
     if mask is None:
@@ -219,8 +341,8 @@ class Concatenate(_Merge):
     for input_i, mask_i in zip(inputs, mask):
       if mask_i is None:
         # Input is unmasked. Append all 1s to masks,
-        # but cast it to uint8 first
-        masks.append(K.cast(K.ones_like(input_i), 'uint8'))
+        # but cast it to bool first
+        masks.append(K.cast(K.ones_like(input_i), 'bool'))
       elif K.ndim(mask_i) < K.ndim(input_i):
         # Mask is smaller than the input, expand it
         masks.append(K.expand_dims(mask_i))
diff --git a/tensorflow/contrib/keras/python/keras/layers/normalization.py b/tensorflow/contrib/keras/python/keras/layers/normalization.py
index 41c618cc79..d429cd6d9b 100644
--- a/tensorflow/contrib/keras/python/keras/layers/normalization.py
+++ b/tensorflow/contrib/keras/python/keras/layers/normalization.py
@@ -154,7 +154,7 @@ class BatchNormalization(Layer):
     broadcast_shape[self.axis] = input_shape[self.axis]
 
     # Determines whether broadcasting is needed.
-    needs_broadcasting = (sorted(reduction_axes) != range(ndim)[:-1])
+    needs_broadcasting = (sorted(reduction_axes) != list(range(ndim))[:-1])
 
     normed, mean, variance = K.normalize_batch_in_training(
         inputs, self.gamma, self.beta, reduction_axes, epsilon=self.epsilon)
diff --git a/tensorflow/contrib/keras/python/keras/layers/pooling.py b/tensorflow/contrib/keras/python/keras/layers/pooling.py
index e31caed3ec..47c88bf4d0 100644
--- a/tensorflow/contrib/keras/python/keras/layers/pooling.py
+++ b/tensorflow/contrib/keras/python/keras/layers/pooling.py
@@ -199,9 +199,9 @@ class MaxPooling2D(_Pooling2D):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
@@ -255,9 +255,9 @@ class AveragePooling2D(_Pooling2D):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
@@ -542,9 +542,9 @@ class GlobalAveragePooling2D(_GlobalPooling2D):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
@@ -577,9 +577,9 @@ class GlobalMaxPooling2D(_GlobalPooling2D):
           one of `channels_last` (default) or `channels_first`.
           The ordering of the dimensions in the inputs.
           `channels_last` corresponds to inputs with shape
-          `(batch, width, height, channels)` while `channels_first`
+          `(batch, height, width, channels)` while `channels_first`
           corresponds to inputs with shape
-          `(batch, channels, width, height)`.
+          `(batch, channels, height, width)`.
           It defaults to the `image_data_format` value found in your
           Keras config file at `~/.keras/keras.json`.
           If you never set it, then it will be "channels_last".
diff --git a/tensorflow/contrib/keras/python/keras/layers/recurrent.py b/tensorflow/contrib/keras/python/keras/layers/recurrent.py
index 06986d3eaa..6301132f4d 100644
--- a/tensorflow/contrib/keras/python/keras/layers/recurrent.py
+++ b/tensorflow/contrib/keras/python/keras/layers/recurrent.py
@@ -105,8 +105,16 @@ class Recurrent(Layer):
       # now model.output_shape == (None, 32)
       # note: `None` is the batch dimension.
 
-      # for subsequent layers, not need to specify the input size:
+      # for subsequent layers, no need to specify the input size:
       model.add(LSTM(16))
+
+      # to stack recurrent layers, you must use return_sequences=True
+      # on any recurrent layer that feeds into another recurrent layer.
+      # note that you only need to specify the input size on the first layer.
+      model = Sequential()
+      model.add(LSTM(64, input_dim=64, input_length=10, return_sequences=True))
+      model.add(LSTM(32, return_sequences=True))
+      model.add(LSTM(10))
   ```
 
   Arguments:
@@ -116,7 +124,8 @@ class Recurrent(Layer):
       return_sequences: Boolean. Whether to return the last output
           in the output sequence, or the full sequence.
       go_backwards: Boolean (default False).
-          If True, process the input sequence backwards.
+          If True, process the input sequence backwards and return the
+          reversed sequence.
       stateful: Boolean (default False). If True, the last state
           for each sample at index i in a batch will be used as initial
           state for the sample of index i in the following batch.
@@ -398,6 +407,7 @@ class SimpleRNN(Recurrent):
       units: Positive integer, dimensionality of the output space.
       activation: Activation function to use.
           If you don't specify anything, no activation is applied
+          If you pass None, no activation is applied
           (ie. "linear" activation: `a(x) = x`).
       use_bias: Boolean, whether the layer uses a bias vector.
       kernel_initializer: Initializer for the `kernel` weights matrix,
@@ -547,7 +557,7 @@ class SimpleRNN(Recurrent):
 
   def get_constants(self, inputs, training=None):
     constants = []
-    if self.implementation == 0 and 0 < self.dropout < 1:
+    if self.implementation != 0 and 0 < self.dropout < 1:
       input_shape = K.int_shape(inputs)
       input_dim = input_shape[-1]
       ones = K.ones_like(K.reshape(inputs[:, 0, 0], (-1, 1)))
@@ -619,7 +629,7 @@ class GRU(Recurrent):
   Arguments:
       units: Positive integer, dimensionality of the output space.
       activation: Activation function to use.
-          If you don't specify anything, no activation is applied
+          If you pass None, no activation is applied
           (ie. "linear" activation: `a(x) = x`).
       recurrent_activation: Activation function to use
           for the recurrent step.
@@ -792,7 +802,7 @@ class GRU(Recurrent):
 
   def get_constants(self, inputs, training=None):
     constants = []
-    if self.implementation == 0 and 0 < self.dropout < 1:
+    if self.implementation != 0 and 0 < self.dropout < 1:
       input_shape = K.int_shape(inputs)
       input_dim = input_shape[-1]
       ones = K.ones_like(K.reshape(inputs[:, 0, 0], (-1, 1)))
@@ -861,7 +871,7 @@ class GRU(Recurrent):
         if self.use_bias:
           x_z = K.bias_add(x_z, self.bias_z)
           x_r = K.bias_add(x_r, self.bias_r)
-          x_h = K.bias_add(x_r, self.bias_h)
+          x_h = K.bias_add(x_h, self.bias_h)
       else:
         raise ValueError('Unknown `implementation` mode.')
       z = self.recurrent_activation(x_z + K.dot(h_tm1 * rec_dp_mask[0],
@@ -924,7 +934,7 @@ class LSTM(Recurrent):
   Arguments:
       units: Positive integer, dimensionality of the output space.
       activation: Activation function to use.
-          If you don't specify anything, no activation is applied
+          If you pass None, no activation is applied
           (ie. "linear" activation: `a(x) = x`).
       recurrent_activation: Activation function to use
           for the recurrent step.
@@ -1127,7 +1137,7 @@ class LSTM(Recurrent):
 
   def get_constants(self, inputs, training=None):
     constants = []
-    if self.implementation == 0 and 0 < self.dropout < 1:
+    if self.implementation != 0 and 0 < self.dropout < 1:
       input_shape = K.int_shape(inputs)
       input_dim = input_shape[-1]
       ones = K.ones_like(K.reshape(inputs[:, 0, 0], (-1, 1)))
diff --git a/tensorflow/contrib/keras/python/keras/layers/wrappers.py b/tensorflow/contrib/keras/python/keras/layers/wrappers.py
index 75b4810e40..eeb67493ee 100644
--- a/tensorflow/contrib/keras/python/keras/layers/wrappers.py
+++ b/tensorflow/contrib/keras/python/keras/layers/wrappers.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 # ==============================================================================
+# pylint: disable=protected-access
 """Wrapper layers: layers that augment the functionality of another layer.
 """
 from __future__ import absolute_import
@@ -19,6 +20,7 @@ from __future__ import division
 from __future__ import print_function
 
 import copy
+import inspect
 
 from tensorflow.contrib.keras.python.keras import backend as K
 from tensorflow.contrib.keras.python.keras.engine import InputSpec
@@ -70,9 +72,10 @@ class Wrapper(Layer):
     return dict(list(base_config.items()) + list(config.items()))
 
   @classmethod
-  def from_config(cls, config):
+  def from_config(cls, config, custom_objects=None):
     from tensorflow.contrib.keras.python.keras.layers import deserialize as deserialize_layer  # pylint: disable=g-import-not-at-top
-    layer = deserialize_layer(config.pop('layer'))
+    layer = deserialize_layer(
+        config.pop('layer'), custom_objects=custom_objects)
     return cls(layer, **config)
 
 
@@ -188,12 +191,15 @@ class Bidirectional(Wrapper):
           If None, the outputs will not be combined,
           they will be returned as a list.
 
+  Raises:
+      ValueError: In case of invalid `merge_mode` argument.
+
   Examples:
 
   ```python
       model = Sequential()
       model.add(Bidirectional(LSTM(10, return_sequences=True), input_shape=(5,
-        10)))
+      10)))
       model.add(Bidirectional(LSTM(10)))
       model.add(Dense(5))
       model.add(Activation('softmax'))
@@ -242,29 +248,47 @@ class Bidirectional(Wrapper):
       shape = self.forward_layer._compute_output_shape(input_shape)  # pylint: disable=protected-access
       return [shape, copy.copy(shape)]
 
-  def call(self, inputs, mask=None):
-    y = self.forward_layer.call(inputs, mask)
-    y_rev = self.backward_layer.call(inputs, mask)
+  def call(self, inputs, training=None, mask=None):
+    kwargs = {}
+    func_args = inspect.getargspec(self.layer.call).args
+    if 'training' in func_args:
+      kwargs['training'] = training
+    if 'mask' in func_args:
+      kwargs['mask'] = mask
+
+    y = self.forward_layer.call(inputs, **kwargs)
+    y_rev = self.backward_layer.call(inputs, **kwargs)
     if self.return_sequences:
       y_rev = K.reverse(y_rev, 1)
     if self.merge_mode == 'concat':
-      return K.concatenate([y, y_rev])
+      output = K.concatenate([y, y_rev])
     elif self.merge_mode == 'sum':
-      return y + y_rev
+      output = y + y_rev
     elif self.merge_mode == 'ave':
-      return (y + y_rev) / 2
+      output = (y + y_rev) / 2
     elif self.merge_mode == 'mul':
-      return y * y_rev
+      output = y * y_rev
     elif self.merge_mode is None:
-      return [y, y_rev]
+      output = [y, y_rev]
+
+    # Properly set learning phase
+    if 0 < self.layer.dropout + self.layer.recurrent_dropout:
+      if self.merge_mode is None:
+        for out in output:
+          out._uses_learning_phase = True
+      else:
+        output._uses_learning_phase = True
+    return output
 
   def reset_states(self):
     self.forward_layer.reset_states()
     self.backward_layer.reset_states()
 
   def build(self, input_shape):
-    self.forward_layer.build(input_shape)
-    self.backward_layer.build(input_shape)
+    with K.name_scope(self.forward_layer.name):
+      self.forward_layer.build(input_shape)
+    with K.name_scope(self.backward_layer.name):
+      self.backward_layer.build(input_shape)
     self.built = True
 
   def compute_mask(self, inputs, mask):
diff --git a/tensorflow/contrib/keras/python/keras/metrics.py b/tensorflow/contrib/keras/python/keras/metrics.py
index d7266c94cf..59d380f73b 100644
--- a/tensorflow/contrib/keras/python/keras/metrics.py
+++ b/tensorflow/contrib/keras/python/keras/metrics.py
@@ -43,12 +43,15 @@ def binary_accuracy(y_true, y_pred):
 
 
 def categorical_accuracy(y_true, y_pred):
-  return K.equal(K.argmax(y_true, axis=-1), K.argmax(y_pred, axis=-1))
+  return K.cast(
+      K.equal(K.argmax(y_true, axis=-1), K.argmax(y_pred, axis=-1)), K.floatx())
 
 
 def sparse_categorical_accuracy(y_true, y_pred):
-  return K.equal(
-      K.max(y_true, axis=-1), K.cast(K.argmax(y_pred, axis=-1), K.floatx()))
+  return K.cast(
+      K.equal(
+          K.max(y_true, axis=-1), K.cast(K.argmax(y_pred, axis=-1),
+                                         K.floatx())), K.floatx())
 
 
 def top_k_categorical_accuracy(y_true, y_pred, k=5):
diff --git a/tensorflow/contrib/keras/python/keras/models.py b/tensorflow/contrib/keras/python/keras/models.py
index 2be4431d03..5289bb732b 100644
--- a/tensorflow/contrib/keras/python/keras/models.py
+++ b/tensorflow/contrib/keras/python/keras/models.py
@@ -207,7 +207,7 @@ def load_model(filepath, custom_objects=None):
       ValueError: In case of an invalid savefile.
   """
   if h5py is None:
-    raise ImportError('`save_model` requires h5py.')
+    raise ImportError('`load_model` requires h5py.')
 
   if not custom_objects:
     custom_objects = {}
@@ -1006,7 +1006,7 @@ class Sequential(Model):
         steps_per_epoch: Total number of steps (batches of samples)
             to yield from `generator` before declaring one epoch
             finished and starting the next epoch. It should typically
-            be equal to the number of unique samples if your dataset
+            be equal to the number of unique samples of your dataset
             divided by the batch size.
         epochs: Integer, total number of iterations on the data.
         verbose: Verbosity mode, 0, 1, or 2.
@@ -1017,8 +1017,10 @@ class Sequential(Model):
             - A tuple (inputs, targets, sample_weights).
         validation_steps: Only relevant if `validation_data`
             is a generator.
-            Number of samples to use from validation generator
-            at the end of every epoch.
+            Number of steps to yield from validation generator
+            at the end of every epoch. It should typically
+            be equal to the number of unique samples of your
+            validation dataset divided by the batch size.
         class_weight: Dictionary mapping class indices to a weight
             for the class.
         max_q_size: Maximum size for the generator queue
@@ -1050,7 +1052,7 @@ class Sequential(Model):
                     # and labels, from each line in the file
                     x, y = process_line(line)
                     yield (x, y)
-                f.close()
+                    f.close()
 
         model.fit_generator(generate_arrays_from_file('/my_file.txt'),
                             samples_per_epoch=10000, epochs=10)
@@ -1119,7 +1121,8 @@ class Sequential(Model):
                         steps,
                         max_q_size=10,
                         workers=1,
-                        pickle_safe=False):
+                        pickle_safe=False,
+                        verbose=0):
     """Generates predictions for the input samples from a data generator.
 
     The generator should return the same kind of data as accepted by
@@ -1136,6 +1139,7 @@ class Sequential(Model):
             relies on multiprocessing, you should not pass
             non picklable arguments to the generator
             as they can't be passed easily to children processes.
+        verbose: verbosity mode, 0 or 1.
 
     Returns:
         A Numpy array of predictions.
@@ -1147,7 +1151,8 @@ class Sequential(Model):
         steps,
         max_q_size=max_q_size,
         workers=workers,
-        pickle_safe=pickle_safe)
+        pickle_safe=pickle_safe,
+        verbose=verbose)
 
   def get_config(self):
     config = []
@@ -1159,9 +1164,9 @@ class Sequential(Model):
     return copy.deepcopy(config)
 
   @classmethod
-  def from_config(cls, config):
+  def from_config(cls, config, custom_objects=None):
     model = cls()
     for conf in config:
-      layer = layer_module.deserialize(conf)
+      layer = layer_module.deserialize(conf, custom_objects=custom_objects)
       model.add(layer)
     return model
diff --git a/tensorflow/contrib/keras/python/keras/preprocessing/image.py b/tensorflow/contrib/keras/python/keras/preprocessing/image.py
index 86c7650a07..de0749ae02 100644
--- a/tensorflow/contrib/keras/python/keras/preprocessing/image.py
+++ b/tensorflow/contrib/keras/python/keras/preprocessing/image.py
@@ -785,7 +785,7 @@ class Iterator(object):
           index_array = np.random.permutation(n)
 
       current_index = (self.batch_index * batch_size) % n
-      if n >= current_index + batch_size:
+      if n > current_index + batch_size:
         current_batch_size = batch_size
         self.batch_index += 1
       else:
diff --git a/tensorflow/contrib/keras/python/keras/utils/generic_utils.py b/tensorflow/contrib/keras/python/keras/utils/generic_utils.py
index c1e0296835..6e83fde2c9 100644
--- a/tensorflow/contrib/keras/python/keras/utils/generic_utils.py
+++ b/tensorflow/contrib/keras/python/keras/utils/generic_utils.py
@@ -172,7 +172,8 @@ def deserialize_keras_object(identifier,
     else:
       fn = module_objects.get(function_name)
       if fn is None:
-        raise ValueError('Unknown ' + printable_module_name, ':' + class_name)
+        raise ValueError('Unknown ' + printable_module_name,
+                         ':' + function_name)
     return fn
   else:
     raise ValueError('Could not interpret serialized ' + printable_module_name +
@@ -215,6 +216,8 @@ def func_load(code, defaults=None, closure=None, globs=None):
   """
   if isinstance(code, (tuple, list)):  # unpack previous dump
     code, defaults, closure = code
+    if isinstance(defaults, list):
+      defaults = tuple(defaults)
   code = marshal.loads(code.encode('raw_unicode_escape'))
   if globs is None:
     globs = globals()
diff --git a/tensorflow/contrib/keras/python/keras/utils/layer_utils.py b/tensorflow/contrib/keras/python/keras/utils/layer_utils.py
index 32e0de7d3d..26878fdd57 100644
--- a/tensorflow/contrib/keras/python/keras/utils/layer_utils.py
+++ b/tensorflow/contrib/keras/python/keras/utils/layer_utils.py
@@ -171,7 +171,7 @@ def count_total_params(layers, layer_set=None):
           [K.count_params(p) for p in layer.trainable_weights])
       non_trainable_count += np.sum(
           [K.count_params(p) for p in layer.non_trainable_weights])
-  return trainable_count, non_trainable_count
+  return int(trainable_count), int(non_trainable_count)
 
 
 def convert_all_kernels_in_model(model):
diff --git a/tensorflow/contrib/keras/python/keras/wrappers/scikit_learn.py b/tensorflow/contrib/keras/python/keras/wrappers/scikit_learn.py
index ecda890fec..323c31aee8 100644
--- a/tensorflow/contrib/keras/python/keras/wrappers/scikit_learn.py
+++ b/tensorflow/contrib/keras/python/keras/wrappers/scikit_learn.py
@@ -194,6 +194,36 @@ class KerasClassifier(BaseWrapper):
   """Implementation of the scikit-learn classifier API for Keras.
   """
 
+  def fit(self, x, y, **kwargs):
+    """Constructs a new model with `build_fn` & fit the model to `(x, y)`.
+
+    Arguments:
+        x : array-like, shape `(n_samples, n_features)`
+            Training samples where n_samples in the number of samples
+            and n_features is the number of features.
+        y : array-like, shape `(n_samples,)` or `(n_samples, n_outputs)`
+            True labels for X.
+        **kwargs: dictionary arguments
+            Legal arguments are the arguments of `Sequential.fit`
+
+    Returns:
+        history : object
+            details about the training history at each epoch.
+
+    Raises:
+        ValueError: In case of invalid shape for `y` argument.
+    """
+    y = np.array(y)
+    if len(y.shape) == 2 and y.shape[1] > 1:
+      self.classes_ = np.arange(y.shape[1])
+    elif (len(y.shape) == 2 and y.shape[1] == 1) or len(y.shape) == 1:
+      self.classes_ = np.unique(y)
+      y = np.searchsorted(self.classes_, y)
+    else:
+      raise ValueError('Invalid shape for y: ' + str(y.shape))
+    self.n_classes_ = len(self.classes_)
+    return super(KerasClassifier, self).fit(x, y, **kwargs)
+
   def predict(self, x, **kwargs):
     """Returns the class predictions for the given test data.
 
@@ -210,7 +240,8 @@ class KerasClassifier(BaseWrapper):
             Class predictions.
     """
     kwargs = self.filter_sk_params(Sequential.predict_classes, kwargs)
-    return self.model.predict_classes(x, **kwargs)
+    classes = self.model.predict_classes(x, **kwargs)
+    return self.classes_[classes]
 
   def predict_proba(self, x, **kwargs):
     """Returns class probability estimates for the given test data.
@@ -261,6 +292,7 @@ class KerasClassifier(BaseWrapper):
             compute accuracy. You should pass `metrics=["accuracy"]` to
             the `.compile()` method of the model.
     """
+    y = np.searchsorted(self.classes_, y)
     kwargs = self.filter_sk_params(Sequential.evaluate, kwargs)
 
     loss_name = self.model.loss