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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 inversion(origin=(0, 0, 0)):
 """ Inversion symmetry operation about axis. Args: origin (3x1 array):
 Origin of the inversion operation. Defaults to [0, 0, 0]. Returns: SymmOp representing an inversion operation about the origin. """

        mat = -np.eye(4)
        mat[3, 3] = 1
        mat[0:3, 3] = 2 * np.array(origin)
        return SymmOp(mat)