input: Write a function to calculate the square root of an integer input. If the input value is not an integer, raise a TypeError 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
  assert square_root(16) == 4.0
  assert square_root('four') # This should raise a TypeError
  assert square_root(4.5) # This should raise a TypeError
output: def square_root(x):
      if not isinstance(x, int):
          raise TypeError('Input must be an integer')
      return x**0.5