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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 value_from_message(self, message):
 """Convert a message to a value instance. Used by deserializers to convert from underlying messages to value of expected user type. Args: message: A message instance of type self.message_type. Returns: Value of self.message_type. """

        if not isinstance(message, self.message_type):
            raise DecodeError('Expected type %s, got %s: %r' %
                              (self.message_type.__name__,
                               type(message).__name__,
                               message))
        return message