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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 appendleft(self, item):
 """Add item to the left side of the GeventDeque. This method does not block. Either the GeventDeque grows to consume available memory, or if this GeventDeque has and is at maxlen, the rightmost item is removed. """

        self._deque.appendleft(item)
        self.notEmpty.set()