def listmofize(x):

    """
    Return x inside a list if it isn't already a list or tuple.
    Otherwise, return x.

    >>> listmofize('abc')
    ['abc']

    >>> listmofize(['abc', 'def'])
    ['abc', 'def']

    >>> listmofize((1,2))
    (1, 2)
    """

    if not isinstance(x, (list, tuple)): return [x]
    else: return x