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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 drag_and_drop(self, source, target):
 """ Holds down the left mouse button on the source element, then moves to the target element and releases the mouse button. :Args: - source: The element to mouse down. - target: The element to mouse up. """

        self.click_and_hold(source)
        self.release(target)
        return self