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

Example Input: Sentence: 'a woman on a cell phone on  city street'. Replace the letter 'e' with 'a' in the sentence.
Example Output: a woman on a call phona on  city straat

Example Input: Sentence: 'a group of young adults are engaged in outdoor exercise'. Replace the letter 'g' with 'n' in the sentence.
Example Output: a nroup of younn adults are ennaned in outdoor exercise

Example Input: Sentence: 'several delta airplanes parked on the landing strip area in front of a renaissance hotel'. Replace the letter 'a' with 'c' in the sentence.
Example Output:
severcl deltc cirplcnes pcrked on the lcnding strip crec in front of c rencisscnce hotel