class Context(dict): def __getitem__(self, k): return super(Context, self).get(k, '{%s}' % k) ctx = Context(source='foo', name='bar') print("{source}/static/{name}-{version}.min.css".format(**ctx))
Standard input is empty
Standard output is empty
Traceback (most recent call last): File "prog.py", line 6, in <module> KeyError: 'version'