21 make errors example into a function

[Scottan]

I've made it into a function and updated some of the text

Any thoughts on replacing:

def check_value(val):
    if val>0 and val<10:
        print('Value: ', val, 'is a digit.')
    elif val==0:
        print('Value ', val, 'is nul')
    else:
        print('Value: ', val, 'is a number.')

with:

def check_sign(val):
    if val == 0:
        print('Value: ', val, 'is zero.')
    elif val > 0:
        print('Value ', val, 'is positive')
    else:
        print('Value: ', val, 'is negative.')

I personally think it's a clearer and less distracting test, see #21.

I also wonder if we should add a note saying it is usually a good idea to put the try / except statements inside the function, but we are going to leave them outside the function for these examples

[github-actions]

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⏱️ Updated at 2026-04-13 11:39:47 +0000

[andrewgait]

I agree that the sign test is likely better in this instance (and if they've done the introductory python course, there's something similar in that), so I would change it to use that test instead.

[andrewgait]

Looks good to me now - approved to merge.