code: def _insertPoint(self, index, position, type="line",
                       smooth=False, name=None, identifier=None, **kwargs):
          
          self.raiseNotImplementedError()
docs: position will be a valid position (x, y).
          type will be a valid type.
          smooth will be a valid boolean.
          name will be a valid name or None.
          identifier will be a valid identifier or None.
          The identifier will not have been tested for uniqueness.
  
          Subclasses must override this method.