code: def from_value(self, value):
          
          if value is None:
              sql_type = NVarCharType(size=1)
          else:
              sql_type = self._from_class_value(value, type(value))
          return sql_type
docs: Function infers TDS type from Python value.
  
          :param value: value from which to infer TDS type
          :return: An instance of subclass of :class:`BaseType`