$1.$ Python class hierarchy:

$$a$.$ Define a 'ParentClass' with a method named 'show$\_$info'.

$$b$.$ Define a 'ChildClass' that inherits from 'ParentClass'.

$2.$ In the 'ParentClass':

a$.$ Define a method 'show$\_$info' with the parameter of 'self'.

b$.$ Inside the method print "This is the ParentClass method."

$3.$ In the 'ChildClass':

$$a$.$ Override the 'show$\_$info' method.

$$b$.$ Inside the overridden method, use 'super$()\text{'}$ to call the 'show$\_$info' method from the parent class.

$$c$.$ After calling the parent class method, print a message "This is the ChildClass method." indicating that it's the 'ChildClass' method:

$4.$ Outside the classes:

$$a$.$ Create an instance of 'ChildClass'.

$$b$.$ Call the 'show$\_$info' method on the instance.