def print_items(x):
    """prec: x is a list or a tuple
postcondtion:  Each item of the list is printed on its own line."""
    #whodunit: Harper Callahan
    if len(x) == 0:
        return
    print(x[0])
    x = x[1:]
    print_items(x)
def print_items(x)
    if len(x) == 0:
        return
    first = x[0]
    rest = x[1:]
    print(first)
    print_list(rest)
print_items(("a", "b", "c"))
print_items("Wonkavision!")