class_docstr: Support Graphite Glat tables
class_docstr_tok: ["Support","Graphite","Glat","tables"]
code: def decompileAttributes3(self, data):
      if self.hasOctaboxes:
          o, data = sstruct.unpack2(
              Glat_format_3_octabox_metrics, data, _Object()
          )
          numsub = bin(o.subboxBitmap).count("1")
          o.subboxes = []
          for b in range(numsub):
              if len(data) >= 8:
                  subbox, data = sstruct.unpack2(
                      Glat_format_3_subbox_entry, data, _Object()
                  )
                  o.subboxes.append(subbox)
      attrs = self.decompileAttributes12(data, Glat_format_23_entry)
      if self.hasOctaboxes:
          attrs.octabox = o
      return attrs
  
imports: from fontTools.misc import sstruct
  from fontTools.misc.fixedTools import floatToFixedToStr
  from fontTools.misc.textTools import safeEval
  from functools import partial
  from .None import DefaultTable
  from .None import grUtils
  import struct
label_desc: Use image node_id 4 for calling the table_G__l_a_t obj's underlying member method code with example usage: obj.decompileAttributes3(data) and returns: attrs