new_contents: def is_krampus(n):
      p = str(n**2)
      l_p = len(p)
  
      for i in range(1, l_p - 1):
          p_1 = int(p[:i])
          p_2 = int(p[i:])
          if p_1 and p_2 and p_1 + p_2 == n:
              return True
  
      return False
  
  
  def test_is_krampus():
      assert is_krampus(45)
      assert not is_krampus(100)
  
  
  if __name__ == '__main__':
      s = 0
  
      for n in open('input/09').readlines():
          n = int(n.strip())
  
          if is_krampus(n):
              s += n
  
      print(s)
  
subject: Solve Knowit2019/09