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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 rotate(compound, theta, around):
 """Rotate a compound around an arbitrary vector. Parameters compound : mb.Compound The compound being rotated. theta : float The angle by which to rotate the compound, in radians. around : np.ndarray, shape=(3,), dtype=float The vector about which to rotate the compound. """

    around = np.asarray(around).reshape(3)
    if np.array_equal(around, np.zeros(3)):
        raise ValueError('Cannot rotate around a zero vector')
    atom_positions = compound.xyz_with_ports
    atom_positions = Rotation(theta, around).apply_to(atom_positions)
    compound.xyz_with_ports = atom_positions