code: def find_token(sentence, start_pos):
      found_tok = None
      for tok in sentence:
          if tok.idx == start_pos:
              found_tok = tok
              break
      return found_tok
  
file_path: fairseq/examples/roberta/wsc/wsc_utils.py
imports: import json
  from functools import lru_cache
label_desc: Use image node_id 3 for calling a global function with example usage: find_token(sentence, start_pos) and returns: found_tok