Check for the Existence of Elements

00:00 In this lesson, you’ll take a look at how you can check for the existence of values using the in keyword. That’s something I just wanted to mention briefly.

00:08 You can use the in keyword to check whether a value is inside of a tuple. And you can do that, like, so let’s say we have a vowels tuple that contains the vowels of the English alphabet, "a", "e", "i", "o", "u".

00:24 And then you could go ahead and say, is "o" in vowels by just typing the string "o" in vowels, and then Python is going to return True because "o" is an element in the tuple vowels.

00:39 Then to try the opposite, if I say "x", the character "x" in vowels, then Python’s going to return False because that’s not part of the vowels tuple.

00:50 Now you can do this all with non-string data. So again, so there are numbers

00:59 1, 2, 3, so a tuple that consists of the integers 1, 2, and 3. And similarly by typing 1 in numbers and Python’s going to return True.

01:10 And if you try 100 in numbers—

01:15 got to spell numbers correctly, let’s try again—100 in numbers, then Python returns False. And this is how you can check whether a value is an element of a tuple by using the in keyword.