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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 down(self, point):
 """Record an initial mouse press at a given point. Parameters point : (2,) int The x and y pixel coordinates of the mouse press. """

        self._pdown = np.array(point, dtype=np.float32)
        self._pose = self._n_pose
        self._target = self._n_target