input: Write a function to modify the provided Python code so that it raises an exception if the input value is not an integer. The function should take an integer as input and return its square root. If the input is not an integer, a TypeError should be raised with the message 'Input must be an integer'.
  
  def square_root(x):
      if not isinstance(x, int):
          raise TypeError('Input must be an integer')
      return x**0.5
  assert square_root(4)==2.0
  assert square_root(9)==3.0
  try:
      square_root('4')
  except TypeError:
      assert True
  else:
      assert False
  try:
      square_root(4.0)
  except TypeError:
      assert True
  else:
      assert False
output: def square_root(x):
      if not isinstance(x, int):
          raise TypeError('Input must be an integer')
      return x**0.5