class_docstr: Base container class.
class_docstr_tok: ["Base","container","class","."]
docstr: Returns the number of elements in the container.
docstr_tok: ["Returns","the","number","of","elements","in","the","container","."]
code: def __len__(self):
      """Returns the number of elements in the container."""
      return len(self._values)
  
imports: import collections
  import sys
label_desc: Use image node_id 3 for calling the BaseContainer obj's underlying member method code with example usage: obj.__len__() and returns: len