class_docstr: DocProto implementation for internal use.
class_docstr_tok: ["DocProto","implementation","for","internal","use","."]
docstr: Returns the number of tokens in doc. Raise if self is not tokenized.
docstr_tok: ["Returns","the","number","of","tokens","in","doc",".","Raise","if","self","is","not","tokenized","."]
code: def __len__(self) -> int:
      """Returns the number of tokens in doc. Raise if self is not tokenized."""
      return len(unwrap(self.tokens))
  
imports: from dataclasses import dataclass, field
  from typing import Any, Dict, Iterator, List, Optional, TypeVar
  from typing_extensions import Protocol, runtime_checkable
label_desc: Use image node_id 3 for calling the Doc obj's underlying member method code with example usage: obj.__len__() and returns: len