code: def test_signed_integers(self):
      self.assertEqual(parse("int8", self.sym), ct.DataShape(ct.int8))
      self.assertEqual(parse("int16", self.sym), ct.DataShape(ct.int16))
      self.assertEqual(parse("int32", self.sym), ct.DataShape(ct.int32))
      self.assertEqual(parse("int64", self.sym), ct.DataShape(ct.int64))
      # self.assertEqual(parse('int128', self.sym),
      #                 ct.DataShape(ct.int128))
      self.assertEqual(parse("int", self.sym), ct.DataShape(ct.int_))
      # 'int' is an alias for 'int32'
      self.assertEqual(parse("int", self.sym), parse("int32", self.sym))
      self.assertEqual(
          parse("intptr", self.sym), ct.DataShape(ct.intptr)
      )
  
imports: from __future__ import absolute_import, division, print_function
  import unittest
  import pytest
  from datashader import datashape
  from datashader.datashape.util.testing import assert_dshape_equal
  from datashader.datashape.parser import parse
  from datashader.datashape import coretypes
  from datashader.datashape import DataShapeSyntaxError
label_desc: Use image node_id 3 for calling the TestDataShapeParseBasicDType obj's underlying member method code with example usage: obj.test_signed_integers() without return types