print("hello world".find("ll"))
print("hello world".find("ll", None))
print("hello world".find("ll", 1))
print("hello world".find("ll", 1, None))
print("hello world".find("ll", None, None))
print("hello world".find("ll", 1, -1))
print("hello world".find("ll", 1, 1))
print("hello world".find("ll", 1, 2))
print("hello world".find("ll", 1, 3))
print("hello world".find("ll", 1, 4))
print("hello world".find("ll", 1, 5))