code: def check_points_type(self, type_class):
          
          for point in self.points:
              if (point.value is not None
                      and not isinstance(point.value, type_class)):
                  return False
          return True
docs: Check that each point's value is an instance of `type_class`.
  
          `type_class` should typically be a Value type, i.e. one that extends
          :class: `opencensus.metrics.export.value.Value`.
  
          :type type_class: type
          :param type_class: Type to check against.
  
          :rtype: bool
          :return: Whether all points are instances of `type_class`.