code: def setupCFF2Regions(self, regions):
      from .varLib.builder import (
          buildVarRegionList,
          buildVarData,
          buildVarStore,
      )
      from .cffLib import VarStoreData
  
      assert "fvar" in self.font, "fvar must to be set up first"
      assert "CFF2" in self.font, "CFF2 must to be set up first"
      axisTags = [a.axisTag for a in self.font["fvar"].axes]
      varRegionList = buildVarRegionList(regions, axisTags)
      varData = buildVarData(
          list(range(len(regions))), None, optimize=False
      )
      varStore = buildVarStore(varRegionList, [varData])
      vstore = VarStoreData(otVarStore=varStore)
      topDict = self.font["CFF2"].cff.topDictIndex[0]
      topDict.VarStore = vstore
      for fontDict in topDict.FDArray:
          fontDict.Private.vstore = vstore
  
imports: from .ttLib import TTFont, newTable
  from .ttLib.tables._c_m_a_p import cmap_classes
  from .ttLib.tables._g_l_y_f import flagCubic
  from .ttLib.tables.O_S_2f_2 import Panose
  from .misc.timeTools import timestampNow
  import struct
  from collections import OrderedDict
label_desc: Use image node_id 13 for calling the FontBuilder obj's underlying member method code with example usage: obj.setupCFF2Regions(regions) without return types