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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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