Question

Given this set and an input GET parameter that indicates a chosen fruit

fruit = {'apple', 'banana', 'orange', 'pear'}

Is there a compact way to do this in one line in python?

chosen = request_obj.get('fruit', '')

if chosen not in fruit:
    chosen = ''

Answer 1

Here’s another way:

>>> fruit = {'apple','banana','orange','pear'}
>>> d = {'fruit': 'apple'}
>>> d['fruit'] if 'fruit' in d and d['fruit'] in fruit else ''
'apple'
>>> d['fruit'] = 'watermellon'
>>> d['fruit'] if 'fruit' in d and d['fruit'] in fruit else ''
''

Honestly, though, I think what you have is more readable and the better choice.