path: "tensorflow.train.FeatureLists.FeatureListEntry"
tf_proto {
  descriptor {
    name: "FeatureListEntry"
    field {
      name: "key"
      number: 1
      label: LABEL_OPTIONAL
      type: TYPE_STRING
    }
    field {
      name: "value"
      number: 2
      label: LABEL_OPTIONAL
      type: TYPE_MESSAGE
      type_name: ".tensorflow.FeatureList"
    }
    options {
      map_entry: true
    }
  }
}