Remove inappropriate dict/list key/value swap instruction from readme

Author: Julian Sequeira

days/07-09-data-structures/README.md

@@ -35,13 +35,11 @@ Perform the following tasks on the list and dict. The less you look at them, the
 
 - Print out the 27th value in the dictionary.
 
-- Replace the 15th key in the dictionary with the 28th item in the list.
-
 
 ### Time to share what you've accomplished!
 
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