I'm a bit too terrified of even attempting to write a PEP for it, but I kind of wish it could be possible to index a Python dict using a non-keyed iterable (list, tuple, set) and get a dict as a result of it.
Something like this:
dict[list] => dict_where_keys_in_list
An alternative idea could be extending set ops to allow dicts in the rhs, so:
dict & set => dict_where_keys_in_set
dict - set => dict_where_keys_not_in_set
But the new dict needs to preserve insertion order of the original dict.