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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 unpack_kraus_matrix(m):
 """ Helper to optionally unpack a JSON compatible representation of a complex Kraus matrix. :param Union[list,np.array] m: The representation of a Kraus operator. Either a complex square matrix (as numpy array or nested lists) or a JSON-able pair of real matrices (as nested lists) representing the element-wise real and imaginary part of m. :return: A complex square numpy array representing the Kraus operator. :rtype: np.array """

        m = np.asarray(m, dtype=complex)
        if m.ndim == 3:
            m = m[0] + 1j * m[1]
        if not m.ndim == 2:  # pragma no coverage
            raise ValueError("Need 2d array.")
        if not m.shape[0] == m.shape[1]:  # pragma no coverage
            raise ValueError("Need square matrix.")
        return m