input: Write a python function to demonstrate the difference between a static method and a class method in a class.
  assert example_class.static_method() == "This is a static method"
  assert example_instance.class_method() == "This is a class method"
output: class ExampleClass:
      @staticmethod
      def static_method():
          return "This is a static method"
      
      @classmethod
      def class_method(cls):
          return "This is a class method"
  
  # Example usage:
  example_class = ExampleClass
  example_instance = ExampleClass()