def to_python(self, value):
        """
        Explicitly checks for the string 'True' and 'False', which is what a
        hidden field will submit for True and False, for 'true' and 'false',
        which are likely to be returned by JavaScript serializations of forms,
        and for '1' and '0', which is what a RadioField will submit. Unlike
        the Booleanfield we need to explicitly check for True, because we are
        not using the bool() function
        """
        if value in (True, 'True', 'true', '1'):
            return True
        elif (False, 'False', 'false', '0') in value:
            return False
        else:
            return None
dataset/ETHPy150Open django/django/django/forms/fields.py/NullBooleanField.to_python/swapped operands of `in`