Clean up `scripts/check.py` — junk comments and `print(func1)` never calls the function

[utk2103]

scripts/check.py is not usable as a teaching example.

def func1():
    # Why: Placeholder function for structure
    # utka
    # utkasfjh      <- leftover keyboard-mashing
    # jlfdjlj
    # jrlfjl
    print(func1)    # prints "<function func1 at 0x...>", not a call

Two problems: four lines of junk comments, and print(func1) prints the function object — which is exactly the mistake beginners make and then get confused by. A file named check.py also tells nobody what it demonstrates.

What to do

• Delete the junk comments.
• Make the function do something real and print its return value.
• Add a short comment contrasting print(func1) (the object) with print(func1()) (the result) — turn the bug into the lesson.
• Rename the file to what it teaches, e.g. functions_and_input_demo.py, and update any reference to it.

Good first issue.