code: def toXML(self, writer, ttFont):
      data = tostr(self.data)
      # removing null bytes. XXX needed??
      data = data.split("\0")
      data = strjoin(data)
      writer.begintag("source")
      writer.newline()
      writer.write_noindent(data)
      writer.newline()
      writer.endtag("source")
      writer.newline()
  
imports: from fontTools.misc.textTools import strjoin, tobytes, tostr
  from .None import DefaultTable
label_desc: Use image node_id 1 for calling the asciiTable obj's underlying member method code with example usage: obj.toXML(writer, ttFont) without return types