code: def test_sub(self):
      self.assertEqual(1j - int(+1), complex(-1, 1))
      self.assertEqual(1j - int(-1), complex(1, 1))
      self.assertRaises(OverflowError, operator.sub, 1j, 10**1000)
      self.assertRaises(TypeError, operator.sub, 1j, None)
      self.assertRaises(TypeError, operator.sub, None, 1j)
  
imports: import unittest
  import sys
  from test import support
  from test.test_grammar import VALID_UNDERSCORE_LITERALS, INVALID_UNDERSCORE_LITERALS
  from random import random
  from math import atan2, isnan, copysign
  import operator
label_desc: Use image node_id 13 for calling the ComplexTest obj's underlying member method code with example usage: obj.test_sub() without return types