Definition: In this task, you need to remove 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: 'several boot designed flower planters on sticks with different types of flowers in them'. Remove all words of length '9' in the given sentence.

several boot designed flower planters on sticks with types of flowers in them