code: def list(
      github, force_reload=False, skip_validation=False, trust_repo=None
  ):
      r"""
      List all callable entrypoints available in the repo specified by ``github``.
  
      Args:
          github (str): a string with format "repo_owner/repo_name[:ref]" with an optional
              ref (tag or branch). If ``ref`` is not specified, the default branch is assumed to be ``main`` if
              it exists, and otherwise ``master``.
              Example: 'pytorch/vision:0.10'
          force_reload (bool, optional): whether to discard the existing cache and force a fresh download.
              Default is ``False``.
          skip_validation (bool, optional): if ``False``, torchhub will check that the branch or commit
              specified by the ``github`` argument properly belongs to the repo owner. This will make
              requests to the GitHub API; you can specify a non-default GitHub token by setting the
              ``GITHUB_TOKEN`` environment variable. Default is ``False``.
          trust_repo (bool, str or None): ``"check"``, ``True``, ``False`` or ``None``.
              This parameter was introduced in v1.12 and helps ensuring that users
              only run code from repos that they trust.
  
              - If ``False``, a prompt will ask the user whether the repo should
                be trusted.
              - If ``True``, the repo will be added to the trusted list and loaded
                without requiring explicit confirmation.
              - If ``"check"``, the repo will be checked against the list of
                trusted repos in the cache. If it is not present in that list, the
                behaviour will fall back onto the ``trust_repo=False`` option.
              - If ``None``: this will raise a warning, inviting the user to set
                ``trust_repo`` to either ``False``, ``True`` or ``"check"``. This
                is only present for backward compatibility and will be removed in
                v2.0.
  
              Default is ``None`` and will eventually change to ``"check"`` in v2.0.
  
      Returns:
          list: The available callables entrypoint
  
      Example:
          >>> # xdoctest: +REQUIRES(env:TORCH_DOCTEST_HUB)
          >>> entrypoints = torch.hub.list('pytorch/vision', force_reload=True)
      """
      repo_dir = _get_cache_or_reload(
          github,
          force_reload,
          trust_repo,
          "list",
          verbose=True,
          skip_validation=skip_validation,
      )
  
      with _add_to_sys_path(repo_dir):
          hubconf_path = os.path.join(repo_dir, MODULE_HUBCONF)
          hub_module = _import_module(MODULE_HUBCONF, hubconf_path)
  
      # We take functions starts with '_' as internal helper functions
      entrypoints = [
          f
          for f in dir(hub_module)
          if callable(getattr(hub_module, f)) and not f.startswith("_")
      ]
  
      return entrypoints
  
imports: import contextlib
  import errno
  import hashlib
  import json
  import os
  import re
  import shutil
  import sys
  import tempfile
  import torch
  import uuid
  import warnings
  import zipfile
  from pathlib import Path
  from typing import Dict, Optional, Any
  from urllib.error import HTTPError, URLError
  from urllib.request import urlopen, Request
  from urllib.parse import urlparse
  from torch.serialization import MAP_LOCATION
label_desc: Use image node_id 17 for calling a global function with example usage: list(github, force_reload, skip_validation, trust_repo) and returns: entrypoints