def _is_real(A):
    try:
        if (A.dtype == np.complex128):
            return False
        elif (A.dtype == np.float64):
            return True
        else:
            raise _DTYPE_ERROR
    except AttributeError as e:
        raise _TYPE_ERROR from e
def _is_real(A):
    try:
        if (A.dtype == np.complex128):
            return False
        elif (A.dtype == np.float64):
            return True
        else:
            raise _DTYPE_ERROR
    except AttributeError as e:
        raise _TYPE_ERROR from e