The function f(x) takes a word as input and applies a substitution cipher to it. Each letter in the input word is replaced by a corresponding letter in a predefined word or phrase. The predefined words or phrases are:

* Shave for "The Barber of Seville"
* Oil for "UAE"
* Kangaroo for "Australia"
* Love for "Lena"
* Mexico for "L\u00f3pez Obrador"
* Read for "book"
* Sushi for "Tokyo"
* Wine for "Portugal"
* Olive oil for "Greece"

