def ambigcutters(seq):
    """
    Returns both resolutions of a cut site that has an ambiguous base in
    it, else the single cut site
    """
    resos = []
    if any([i in list("RKSYWM") for i in seq]):
        for base in list("RKSYWM"):
            if base in seq:
                resos.append(seq.replace(base, AMBIGS[base][0]))
                resos.append(seq.replace(base, AMBIGS[base][1]))
        return resos
    else:
        return [seq, ""]
Returns both resolutions of a cut site that has an ambiguous base in
    it, else the single cut site