Word Sorting

Topics:medium sorting

Write a function which splits a sentence up into a sorted list of words. Capitalization should not affect sort order and punctuation should be ignored.
test not run
(= (__  "Have a nice day.")
   ["a" "day" "Have" "nice"])
test not run
(= (__  "Clojure is a fun language!")
   ["a" "Clojure" "fun" "is" "language"])
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(= (__  "Fools fall for foolish follies.")
   ["fall" "follies" "foolish" "Fools" "for"])

Code which fills in the blank: