def getAlphabet(self):
        s = "".join(map(lambda x: x.mString, self.values())).lower()
        s = re.sub("[%s]" % "".join(self.mGapChars), "", s)
        ss = re.sub("[acgtxn]", "", s)
        if float(len(ss)) < (len(s) * 0.1):
            return "na"
        else:
            return "aa"
Submitting an empty value in the form should save an empty list.
dataset/ETHPy150Open CGATOxford/cgat/CGAT/Mali.py/Mali.getAlphabet--crossover with--dataset/ETHPy150Open potatolondon/djangae/djangae/tests/test_form_fields.py/ListFieldFormsTest.test_save_empty_value_from_form