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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 read(self, timeout=None):
        '''
        Read from the transport. If no data is available, should return None.
        If timeout>0, will only block for `timeout` seconds.
        '''
        # If currently locked, another greenlet is trying to read, so yield
        # control and then return none. Required if a Connection is configured
        # to be synchronous, a sync callback is trying to read, and there's
        # another read loop running read_frames. Without it, the run loop will
        # release the lock but then immediately acquire it again. Yielding
        # control in the reading thread after bytes are read won't fix
        # anything, because it's quite possible the bytes read resulted in a
        # frame that satisfied the synchronous callback, and so this needs to
        # return immediately to first check the current status of synchronous
        # callbacks before attempting to read again.
        if self._read_lock.locked():
            self._read_wait.wait(timeout)
            return None

        self._read_lock.acquire()
        try:
            return super(GeventTransport, self).read(timeout=timeout)
        finally:
            self._read_lock.release()
            self._read_wait.set()
            self._read_wait.clear()