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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 get_closest_box(self, pos):
 """Get the box closest to some position."""

        pos = np.atleast_2d(pos)
        d = np.sum((np.array(self.box_pos) - pos) ** 2, axis=1)
        idx = np.argmin(d)
        return idx