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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 join(self, timeout: float = None) -> bool: """ Joins on the thread associated with the response if it exists, or just returns after a no-op if no thread exists to join. :param timeout: Maximum number of seconds to block on the join before given up and continuing operation. The default `None` value will wait forever. :return: A boolean indicating whether or not a thread existed to join upon. """

        try:
            self.thread.join(timeout)
            return True
        except AttributeError:
            return False