Definition: In this task, you need to reverse all words of a given length in the sentence. The number of letters in a word determine its length. For example, the length of the word "apple" is 5.
Input: Sentence: 'part of one of the pizzas has been eaten and the other pizza has not been touched'. Reverse all words of length '3' in the given sentence.

part of eno of eht pizzas sah been eaten dna eht other pizza sah ton been touched