input: 
  def square_root(x):
      if not isinstance(x, int):
          raise TypeError('Input must be an integer')
      return x**0.5
  
  # Example usage:
  # >>> square_root(4)
  # 2.0
  # >>> square_root('4')
  # TypeError: Input must be an integer
  
output:     if x < 0:
          raise ValueError('Input must be a non-negative integer')