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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 popleft(self, block=True, timeout=None):
 """Remove and return an item from the right side of the GeventDeque. If no elements are present, raises an IndexError. If optional args *block* is True and *timeout* is ``None`` (the default), block if necessary until an item is available. If *timeout* is a positive number, it blocks at most *timeout* seconds and raises the :class:`IndexError` exception if no item was available within that time. Otherwise (*block* is False), return an item if one is immediately available, else raise the :class:`IndexError` exception (*timeout* is ignored in that case). """

        return self._pop(block, timeout, left=True)