code: def parse(contents, tokens=None):
      
      # Shortcut for users who are interested in tokens
      if tokens is None:
          tokens = [t for t in tokenize(contents)]
  
      token_index, body = _ast_worker(tokens, len(tokens), 0, None)
  
      assert token_index == len(tokens)
      assert body.arguments == []
  
      return ToplevelBody(statements=body.statements)
docs: Parse a string called contents for an AST and return it.