code: def resize_dimension(self, name, new_size):
      
      if name not in self.dimension_names:
        raise ValueError("Shape %s does not have dimension named %s"
                         % (self, name))
      return Shape(
          [Dimension(name, new_size) if d.name == name else d
           for d in self.dims])
docs: Returns a copy where one dimension has a different size.