Definition: In this task you will be given a list of numbers. You should remove any number that is not an integer (whole number). If every number is not an whole number then an empty list ("[]") should be returned. Otherwise, answer with the list of whole numbers separated by comma inside brackets.
Input: [-40, 21.29, 6.772, 91, -5.76, 2, 20.955, 18.5, -13]

[-40, 91, 2, -13]