returning an "else" value at the end of a FOR loop

PYTHON: I got an "if" statement nested in a "for" loop. I need to return a defalut value if, at the end of the for loop, no one of the if statement was satisfied.

example: print the missing numbers in a given list or return the number next to the last element in list

list1 = [0, 1, 2, 3, 5, 7]

FOR i in range(list1[0], list1[-1]):

IF (i not in list1):
    print(i)  {#prints 4, 6}

ELSE (if 4, 6 were in list1 and so there were not missing numbers in the range):

print(list1[-1] + 1)   {#prints the number right after the last item of list}

i knew it's possible to do an else statement regarding a while loop, and i was wondering if the for loop has the same possibility