def to_python(self, value):
        """
        Converts the value into a list.
        """
        if not value:
            value = []

        # If a list is set then validated its items
        if isinstance(value, list):
            py_list = self.validate_list(value)
        else:  # try to de-serialize value and expect list and then validate
            try:
                py_list = json.loads(value)

                if not isinstance(py_list, list):
                    raise TypeError

                self.validate_list(py_list)
            except (ValueError, TypeError):
                raise ValidationError(u'Must be a valid list of strings.')

        return py_list
Converts the value into a list.