How to make loop go back to the beginning if test evaluaes to True.

[stullis]

Use a set instead of a list:

def n_nonrepeated(q_of_nums, minimum_number, maximum_number):
    """Generates odd and even numbers, they can't be repeated."""
    printed_numbers = set()

    while len(printed_numbers) < q_of_nums:
        printed_numbers.add(randint(minimum_number, maximum_number))

    return printed_numbers

Please note that there is the possibility of an infinite loop with this. You may want to add some more logic to prevent that.