Map is a common way to transform lists in most programming languages. In Python, map is a function that loops over a list and applies a function (that you provide) to each item. Your function receives ...

So, for example, the key "Father" could have a value of "Bob." Or, more relevantly, a key of "Hits" (or any word) could have a value of 55. In the latter case, the word is given the value of 55.