input: Write a function to modify the given Python code to raise an exception if the input value is not 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('a')
      assert False, "Should have raised an exception"
  except TypeError:
      pass
  
  
  ### Assertions
  - assert square_root(4)==2.0  # Should return 2.0
  - assert square_root(9)==3.0  # Should return 3.0
  - try:
      square_root('a')
      assert False, "Should have raised an exception"
    except TypeError:
      pass
  
  ### Expected Output:
  The function should raise a `TypeError` if the input value is not an integer.
output: def square_root(x):
      if not isinstance(x, int):
          raise TypeError('Input must be an integer')
      return x**0.5