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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _ExtractSymbols(self, descriptors):
 """Pulls out all the symbols from descriptor protos. Args: descriptors: The messages to extract descriptors from. Yields: A two element tuple of the type name and descriptor object. """


    for desc in descriptors:
      yield (_PrefixWithDot(desc.full_name), desc)
      for symbol in self._ExtractSymbols(desc.nested_types):
        yield symbol
      for enum in desc.enum_types:
        yield (_PrefixWithDot(enum.full_name), enum)