code: def _expand_str_alias(path_cfg, alias_dict, overriding_kargs):
      
  
      # e.g.,
      # path_cfg = 'var_cut'
  
      new_path_cfg = alias_dict[path_cfg]
      # e.g., ('ev : {low} <= ev.var[0] < {high}', {'low': 10, 'high': 200})
  
      new_overriding_kargs = dict(alias=path_cfg)
      # e.g., {'alias': 'var_cut'}
  
      new_overriding_kargs.update(overriding_kargs)
      # e.g., {'alias': 'var_cut', 'name': 'var_cut25', 'low': 25}
  
      return expand_path_cfg(new_path_cfg, alias_dict,new_overriding_kargs)
docs: expand a path config given as a string
  
      Args:
          path_cfg (str): an alias
          alias_dict (dict):
          overriding_kargs (dict):