docstr: Returns the number of elements within this List.
docstr_tok: ["Returns","the","number","of","elements","within","this","List","."]
code: def __len__(self):
      """Returns the number of elements within this List."""
      return sum(1 for _ in self)
  
file_path: pytorch-lightning/src/lightning/app/structures/list.py
imports: import typing
  from lightning.app.utilities.app_helpers import _LightningAppRef, _set_child_name
label_desc: Use image node_id 10 for calling the List obj's underlying member method code with example usage: obj.__len__() and returns: sum