docstr: This adds an empty DSIG table to the font to make some MS applications
  happy. This does not properly sign the font.
code: def setupDummyDSIG(self):
      """This adds an empty DSIG table to the font to make some MS applications
      happy. This does not properly sign the font.
      """
      values = dict(
          ulVersion=1,
          usFlag=0,
          usNumSigs=0,
          signatureRecords=[],
      )
      self._initTableWithValues("DSIG", {}, values)
  
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 27 for calling the FontBuilder obj's underlying member method code with example usage: obj.setupDummyDSIG() without return types