code: def toXML(self, writer, ttFont):
      writer.begintag("kernsubtable", format=self.format)
      writer.newline()
      writer.comment("unknown 'kern' subtable format")
      writer.newline()
      writer.dumphex(self.data)
      writer.endtag("kernsubtable")
      writer.newline()
  
imports: from fontTools.ttLib import getSearchRange
  from fontTools.misc.textTools import safeEval, readHex
  from fontTools.misc.fixedTools import fixedToFloat, floatToFixed
  from .None import DefaultTable
  import struct
  import sys
  import array
  import logging
label_desc: Use image node_id 4 for calling the KernTable_format_unkown obj's underlying member method code with example usage: obj.toXML(writer, ttFont) without return types