code: def __validate_datetime_string(self):
          
  
          try:
              try:
                  StrictVersion(self._value)
                  raise TypeConversionError(
                      "invalid datetime string: version string found {}".format(self._value)
                  )
              except ValueError:
                  pass
          except TypeError:
              raise TypeConversionError("invalid datetime string: type={}".format(type(self._value)))
docs: This will require validating version string (such as "3.3.5").
          A version string could be converted to a datetime value if this
          validation is not executed.