code: def _getenv(key, default=None):
      from os import getenv
  
      return getenv(key, default)
  
file_path: sympy/sympy/core/cache.py
imports: from importlib import import_module
  from typing import Callable
  from functools import lru_cache, wraps
label_desc: Use image node_id 4 for calling a global function with example usage: _getenv(key, default) and returns: getenv