def METHOD_NAME(left, right):
    llist = os.listdir(left)
    rlist = os.listdir(right)
    u = {}
    for l in llist:
        u[l] = 1
    for r in rlist:
        u[r] = 1
    for x in sorted([ x for x in list(u.keys()) if x[-4:] != '.pyc' ]):
        if x in llist:
            if x in rlist:
                do_diff(os.path.join(left, x),
                        os.path.join(right, x),
                        recursive)
            else:
                print('Only in %s: %s' % (left, x))
        else:
            print('Only in %s: %s' % (right, x))