Third Attempt: The "while" loop

In this script, I did the "while loop". While loop is actually related to English programming language. It actually is logical. A while loop statement in Python programming language repeatedly executes a target statement as long as the given condition is true. For example: "While a tea is hot, add some ice to cool it. Generally for loop is for specific number of iterations as for while loop, it is valid if the conditions are true. I added index<5 so it reads my questions.

The following is the F5 module:

But this script is unsuccessful(see on the left), everything I typed in will be invalid. =.= This is a failed script.