new_contents: #!/Applications/anaconda/envs/Python3/bin
  
  
  def main():
      # Test suite
      tests = [
          [None, None], # Should throw a TypeError
          [5, 7, 12],
          [-5, -7, -12],
          [5, -7, -2]
      ]
  
      for item in tests:
          try:
              temp_result = sum_two(item[0], item[1])
              if temp_result == item[2]:
                  print('PASSED: sum_two({}, {}) returned {}'.format(item[0], item[1], temp_result))
              else:
                  print('FAILED: sum_two({}, {}) returned {}, should have returned {}'.format(item[0], item[1], temp_result, item[2]))
  
          except TypeError:
              print('PASSED TypeError test')
  
      return 0
  
  
  def sum_two(a, b):
      '''
      Returns the sum of two integers without using the + or - operators
      Input: a, b both integers
      Output: integer
      '''
      if type(a) is not int or type(b) is not int:
          raise TypeError('a and b must be integers')
  
      result = a ^ b
      borrow = (a & b) << 1
      if borrow != 0:
          return sum_two(result, borrow)
      else:
          return result
  
  
  if __name__ == '__main__':
      main()
  
subject: Add sumTwo problem and tests