code: def _log_level_env():
      try:
          return int(os.environ["LOG_LEVEL"])
      except (KeyError, ValueError):
          return None
  
imports: import logging
  import os
  from guild import cli
  from guild import config
  from guild import log
label_desc: Use image node_id 4 for calling a global function with example usage: _log_level_env() and returns: int, None