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: 'a catcher squatting behind a batter who is swinging on a baseball field'. Reverse all words of length '3' in the given sentence.

a catcher squatting behind a batter ohw is swinging on a baseball field