alues copied from the fields in
        the input array with the same name

    Examples
    --------

    >>> from numpy.lib import recfunctions as rfn
    >>> a = np.ones(4, dtype=[('a', 'i4'), ('b', 'f8'), ('c', 'u1')])
    >>> rfn.require_fields(a, [('b', 'f4'), ('c', 'u1')])
    array([(1., 1), (1., 1), (1., 1), (1., 1)],
      dtype=[('b', '<f4'), ('c', 'u1')])
    >>> rfn.require_fields(a, [('b', 'f4'), ('newf', 'u1')])
    array([(1., 0), (1., 0), (1., 0), (1., 0)],
      dtype=[('b', '<f4'), ('newf', 'u1')])

    r0