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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 _protobuf_value_to_string(value):
 """Returns a string representation of given google.protobuf.Value message. Args: value: google.protobuf.Value message. Assumed to be of type 'number', 'string' or 'bool'. """

  value_in_json = json_format.MessageToJson(value)
  if value.HasField("string_value"):
    # Remove the quotations.
    return value_in_json[1:-1]
  return value_in_json