code: def _flag_dim(val, flag_name):
      if isinstance(val, list):
          return _categorical_dim(val, None)
      if isinstance(val, str):
          return _try_function_dim(val, flag_name)
      raise ValueError(val, flag_name)
  
imports: import logging
  import os
  import typing
  import warnings
  from guild import _skopt
  from guild import batch_util
  from guild import flag_util
  from guild import op_util
  from guild import query
label_desc: Use image node_id 7 for calling a global function with example usage: _flag_dim(val, flag_name) and returns: _categorical_dim, _try_function_dim