def right_words(alist, number): #this function accepts a list of strings and a number
    new_list = []  # an empty list to contain the new list generated
    for num in alist:  # a for loop to loop through every
        if len(num) == number: # this returns true if the length of the string is equal to the value of the variable number
            new_list.append(num)

    return new_list   # returns a newly generated list containing the results from the loop


print(right_words([], 4))