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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_by_offset(self, source, xoffset, yoffset):
 """ Holds down the left mouse button on the source element, then moves to the target offset and releases the mouse button. :Args: - source: The element to mouse down. - xoffset: X offset to move to. - yoffset: Y offset to move to. """

        self.click_and_hold(source)
        self.move_by_offset(xoffset, yoffset)
        self.release()
        return self