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.

Example Input: Sentence: 'a cat attentively watching a graphic on a television screen'. Reverse all words of length '7' in the given sentence.
Example Output: a cat attentively watching a cihparg on a television screen

Example Input: Sentence: 'a bathroom with a white bath tub under a mirror'. Reverse all words of length '5' in the given sentence.
Example Output: a bathroom with a etihw bath tub rednu a mirror

Example Input: Sentence: 'a man holding  camera with a hands free umbrella on his head'. Reverse all words of length '7' in the given sentence.
Example Output:
a man gnidloh camera with a hands free umbrella on his head