Touch a cache key
Move an accessed cache key to the most-recent end and return its value.
What you’ll practice
This Level 3 exercise focuses on OrderedDict.move_to_end in the Collections curriculum. Solve the challenge prompt above using clear, idiomatic Python and the relevant language or standard-library tools.
Relevant Python reference: re — Regular expression operations, collections.OrderedDict.
Sample Test Cases
touch(__import__('collections').OrderedDict([('a',1),('b',2)]), 'a')order becomes b, aFurther Reading
Reference Solution
Reveal Reference Solution
def touch(cache, key): cache.move_to_end(key) return cache[key]Pro Tips & Keyboard Shortcuts
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