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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 angular_distance(n1, n2):
 """Return the angular separation between two 3 dimensional vectors. Parameters n1, n2: array-like, shape (3,) Coordinates of two vectors. Their magnitude does not matter. Returns ------- d_sigma: float Angle between n1 and n2 in radians. """

    return np.arctan2(vector.vector_mag(np.cross(n1, n2)), np.dot(n1, n2))