new_contents: import unittest
  
  from pybitcointools import main
  
  from node import arithmetic
  
  
  class TestArithmetic(unittest.TestCase):
  
      @classmethod
      def setUpClass(cls):
          cls.privkey_hex = (
              "e9873d79c6d87dc0fb6a5778633389f4453213303da61f20bd67fc233aa33262"
          )
  
      def test_privtopub(self):
          pubkey_hex1 = arithmetic.privtopub(self.privkey_hex)
          pubkey_hex2 = main.privkey_to_pubkey(self.privkey_hex)
  
          self.assertEqual(pubkey_hex1, pubkey_hex2)
  
      def test_changebase(self):
          pubkey_hex = arithmetic.privtopub(self.privkey_hex)
          pubkey_bin1 = main.changebase(pubkey_hex, 16, 256)
          pubkey_bin2 = arithmetic.changebase(pubkey_hex, 16, 256)
  
          self.assertEqual(pubkey_bin1, pubkey_bin2)
  
  
  if __name__ == "__main__":
      unittest.main()
  
subject: Test node.arithmetic.