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 man playing at a baseball game is swinging the bat'. Reverse all words of length '8' in the given sentence.

a man playing at a llabesab game is gnigniws the bat