List Twist

mediumpy_classes

Implement ListTwist, a collections.UserList subclass with extra virtual attributes — exposed only through __getattr__ / __setattr__ (do not declare them as properties or methods):

reversed / R — the list reversed (a new plain list).
first / F — get or set the first element.
last / L — get or set the last element.
size / S — get or set the length: shrinking truncates, growing pads with None.

The shortcuts must always reflect the current contents (after append, pop, slicing, etc.).

Your solution

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Hints

Hint 1

Subclass collections.UserList and intercept the shortcut names in __getattr__ (read) and __setattr__ (write).

Hint 2

In __setattr__, route real attributes (like 'data') to super().__setattr__; for 'size', truncate or pad self.data with None.

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