code: def _delete_empty_subrs(private_dict):
      if hasattr(private_dict, "Subrs") and not private_dict.Subrs:
          if "Subrs" in private_dict.rawDict:
              del private_dict.rawDict["Subrs"]
          del private_dict.Subrs
  
imports: from fontTools.misc import psCharStrings
  from fontTools import ttLib
  from fontTools.pens.basePen import NullPen
  from fontTools.misc.roundTools import otRound
  from fontTools.misc.loggingTools import deprecateFunction
  from fontTools.subset.util import _add_method, _uniq_sort
label_desc: Use image node_id 8 for calling a global function with example usage: _delete_empty_subrs(private_dict) without return types