code: def toXML(self, writer, ttFont):
      name = (
          ttFont["name"].getDebugName(self.subfamilyNameID)
          if "name" in ttFont
          else None
      )
      if name is not None:
          writer.newline()
          writer.comment(name)
          writer.newline()
      psname = (
          ttFont["name"].getDebugName(self.postscriptNameID)
          if "name" in ttFont
          else None
      )
      if psname is not None:
          writer.comment("PostScript: " + psname)
          writer.newline()
      if self.postscriptNameID == 0xFFFF:
          writer.begintag(
              "NamedInstance",
              flags=("0x%X" % self.flags),
              subfamilyNameID=self.subfamilyNameID,
          )
      else:
          writer.begintag(
              "NamedInstance",
              flags=("0x%X" % self.flags),
              subfamilyNameID=self.subfamilyNameID,
              postscriptNameID=self.postscriptNameID,
          )
      writer.newline()
      for axis in ttFont["fvar"].axes:
          writer.simpletag(
              "coord",
              axis=axis.axisTag,
              value=fl2str(self.coordinates[axis.axisTag], 16),
          )
          writer.newline()
      writer.endtag("NamedInstance")
      writer.newline()
  
imports: from fontTools.misc import sstruct
  from fontTools.misc.fixedTools import fixedToFloat, floatToFixed, floatToFixedToStr, strToFixedToFloat
  from fontTools.misc.textTools import Tag, bytesjoin, safeEval
  from fontTools.ttLib import TTLibError
  from .None import DefaultTable
  import struct
label_desc: Use image node_id 4 for calling the NamedInstance obj's underlying member method code with example usage: obj.toXML(writer, ttFont) without return types