input: Write a function to modify the given Python code that calculates the square root of a number and raise an exception if the input value is not an integer. If the input is an integer, return the square root of the number.
  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
  assert square_root('a')
output: def square_root(x):
      if not isinstance(x, int):
          raise TypeError('Input must be an integer')
      return x**0.5