Sorting list of lists with string and int

[Otbredbaron]

actually, the easiest way would be to add sorted to your line 5 list comprehension

a = [sorted(input().split()) for i in range(n)]

this way you always get the number as element with index 0 because when sorting '0' to '9' always go before 'A'

def parse_data(item):
    return (int(item[0]), item[1])


data = ['red 10', '10 blue', 'green 7']
data = [parse_data(sorted(item.split())) for item in data]
output = [cup for radius, cup in sorted(data)]
print('\n'.join(output))

note that sample output in your assignment is NOT correct

It is correct because if it's in the format number color, then number need to be divided by 2 so it will be 5.

Why do we need to be explicit and write except ValueError?

I'm not sure I understand exactly what you mean, but here I know that if i[1] contains anything that is not convertible to an integer the call to int() will raise ValueError. In such a case, I always catch the exact exception because I don't want to catch anything else. For example if for some reason there is no i[1], python will throw KeyError and I don't want to catch this at this point. For debugging purposes, it is always better to let unexpected exceptions propagate.

I see now, I need to get used to this try except thing.