In this task, you need to replace a letter in the sentence with another given letter.

Example Input: Sentence: 'a refrigerator with both its doors open in a kitchen'. Replace the letter 'o' with 'x' in the sentence.
Example Output: a refrigeratxr with bxth its dxxrs xpen in a kitchen

Example Input: Sentence: 'a woman is playing tennis on the tennis court'. Replace the letter 'r' with 'z' in the sentence.
Example Output: a woman is playing tennis on the tennis couzt

Example Input: Sentence: 'a window above a wooden table with a vase containing a white flower'. Replace the letter 'o' with 'i' in the sentence.
Example Output:
a windiw abive a wiiden table with a vase cintaining a white fliwer