It's possible to use the command media-effectiveness whith a non existing hasthag as an user and it won't throw any errors, it provids a quite weird result instead.
It would be usefull to test the hashtag and to throw an error message if it does not exist, it would improve the user experience and the effectiveness of the command. I think it's more than just an esthetic aspect of the code but a general enhancement of the user experience.
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