input: from typing import List
  
  
  def square_root(x):
      """
      Returns the square root of the integer input 'x'
      If 'x' is not an integer, raise a TypeError with the message 'Input must be an integer'
      >>> square_root(4)
      2.0
      >>> square_root('4')
      Traceback (most recent call last):
          ...
      TypeError: Input must be an integer
      >>> square_root(9.0)
      Traceback (most recent call last):
          ...
      TypeError: Input must be an integer
      """
      if not isinstance(x, int):
          raise TypeError('Input must be an integer')
      return x**0.5
  
output:     if not isinstance(x, int):
          raise TypeError('Input must be an integer')
      return x**0.5