code: def mapMaybe(
      func: Callable[[T], Optional[S]], xs: Iterable[T]
  ) -> Iterator[S]:
      for x in xs:
          r = func(x)
          if r is not None:
              yield r
  
imports: import contextlib
  import functools
  import hashlib
  import os
  import re
  import sys
  import textwrap
  from argparse import Namespace
  from dataclasses import fields, is_dataclass
  from enum import auto, Enum
  from typing import Any, Callable, Dict, Generic, Iterable, Iterator, List, Literal, NoReturn, Optional, Sequence, Set, Tuple, TypeVar, Union
  from typing_extensions import Self
  from torchgen.code_template import CodeTemplate
label_desc: Use image node_id 2 for calling a global function with example usage: mapMaybe(func, xs) without return types