code: def __len__(self):
      return len(self._map)
  
file_path: catboost/contrib/python/fonttools/fontTools/ttLib/tables/_h_d_m_x.py
imports: from fontTools.misc import sstruct
  from fontTools.misc.textTools import bytechr, byteord, strjoin
  from .None import DefaultTable
  import array
  from collections.abc import Mapping
label_desc: Use image node_id 3 for calling the _GlyphnamedList obj's underlying member method code with example usage: obj.__len__() and returns: len