Write a function that returns True if the first string is the second string stretched, and False otherwise. A stretch is to repeat each character in a string the same number of times.
is_stretched("pppaaannndddaaa", "panda") ➞ True
is_stretched("sssshhiipp", "ship") ➞ False
is_stretched("magnet", "magnet") ➞ True
is_stretched("magneto", "magnet") ➞ False