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diff --git a/doc/tools/coqrst/repl/coqtop.py b/doc/tools/coqrst/repl/coqtop.py
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+++ b/doc/tools/coqrst/repl/coqtop.py
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+##########################################################################
+##         #   The Coq Proof Assistant / The Coq Development Team       ##
+##  v      #   INRIA, CNRS and contributors - Copyright 1999-2018       ##
+## <O___,, #       (see CREDITS file for the list of authors)           ##
+##   \VV/  ###############################################################
+##    //   #    This file is distributed under the terms of the         ##
+##         #     GNU Lesser General Public License Version 2.1          ##
+##         #     (see LICENSE file for the text of the license)         ##
+##########################################################################
+"""
+Drive coqtop with Python!
+=========================
+
+This module is a simple pexpect-based driver for coqtop, based on the old
+REPL interface.
+"""
+
+import os
+import re
+
+import pexpect
+
+class CoqTop:
+    """Create an instance of coqtop.
+
+    Use this as a context manager: no instance of coqtop is created until
+    you call `__enter__`.  coqtop is terminated when you `__exit__` the
+    context manager.
+
+    Sentence parsing is very basic for now (a "." in a quoted string will
+    confuse it).
+    """
+
+    COQTOP_PROMPT = re.compile("\r\n[^< ]+ < ")
+
+    def __init__(self, coqtop_bin=None, color=False, args=None) -> str:
+        """Configure a coqtop instance (but don't start it yet).
+
+        :param coqtop_bin: The path to coqtop; uses $COQBIN by default, falling back to "coqtop"
+        :param color:      When True, tell coqtop to produce ANSI color codes (see
+                           the ansicolors module)
+        :param args:       Additional arugments to coqtop.
+        """
+        self.coqtop_bin = coqtop_bin or os.path.join(os.getenv('COQBIN', ""), "coqtop")
+        if not pexpect.utils.which(self.coqtop_bin):
+            raise ValueError("coqtop binary not found: '{}'".format(self.coqtop_bin))
+        self.args = (args or []) + ["-boot", "-color", "on"] * color
+        self.coqtop = None
+
+    def __enter__(self):
+        if self.coqtop:
+            raise ValueError("This module isn't re-entrant")
+        self.coqtop = pexpect.spawn(self.coqtop_bin, args=self.args, echo=False, encoding="utf-8")
+        # Disable delays (http://pexpect.readthedocs.io/en/stable/commonissues.html?highlight=delaybeforesend)
+        self.coqtop.delaybeforesend = 0
+        self.next_prompt()
+        return self
+
+    def __exit__(self, type, value, traceback):
+        self.coqtop.kill(9)
+
+    def next_prompt(self):
+        "Wait for the next coqtop prompt, and return the output preceeding it."
+        self.coqtop.expect(CoqTop.COQTOP_PROMPT, timeout = 10)
+        return self.coqtop.before
+
+    def sendone(self, sentence):
+        """Send a single sentence to coqtop.
+
+        :sentence: One Coq sentence (otherwise, Coqtop will produce multiple
+                   prompts and we'll get confused)
+        """
+        # Suppress newlines, but not spaces: they are significant in notations
+        sentence = re.sub(r"[\r\n]+", " ", sentence).strip()
+        self.coqtop.sendline(sentence)
+        try:
+            output = self.next_prompt()
+        except:
+            print("Error while sending the following sentence to coqtop: {}".format(sentence))
+            raise
+        # print("Got {}".format(repr(output)))
+        return output
+
+def sendmany(*sentences):
+    """A small demo: send each sentence in sentences and print the output"""
+    with CoqTop() as coqtop:
+        for sentence in sentences:
+            print("=====================================")
+            print(sentence)
+            print("-------------------------------------")
+            response = coqtop.sendone(sentence)
+            print(response)
+
+def main():
+    """Run a simple performance test and demo `sendmany`"""
+    with CoqTop() as coqtop:
+        for _ in range(200):
+            print(repr(coqtop.sendone("Check nat.")))
+        sendmany("Goal False -> True.", "Proof.", "intros H.",
+                 "Check H.", "Chchc.", "apply I.", "Qed.")
+
+if __name__ == '__main__':
+    main()