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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 append(self, item):
 """Add item to the right 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 leftmost item is removed. """

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