userlist_import.py shows how to use UserList as a superclass for a new list-like object. In this case, we are going to create a class that allows a list to be added by simply assigning values to it, rather than having to call the append() function:
First, in line 11, UserList must be imported from the collections module.
Next, the ExtendList class is created in line 12 as a subclass of UserList. This provides list functionality to any ExtendList instance. A setter method is created, accepting an integer and a value. If the integer provided equals the length of the list, then the value argument is appended to the list. ...
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