A generic version of listify that can take any type like list, set, dict

collect.py

import functools
import types


def collect(collection_type):
    """A decorator that will collect stuff from a generator.  For example,

    >>> def tuple_generator():
    ...     yield ('a', 'b')
    ...     yield ('c', 'd')
    ...
    >>> collect(dict)(tuple_generator)()
    {'a': 'b', 'c': 'd'}
    >>> collect(list)(tuple_generator)()
    [('a', 'b'), ('c', 'd')]
    >>> collect(set)(tuple_generator)()
    {('c', 'd'), ('a', 'b')}

    """
    def collectify(func):
        @functools.wraps(func)
        def new_func(*args, **kwargs):
            r = func(*args, **kwargs)
            if r is None:
                return collection_type()
            if isinstance(r, types.GeneratorType):
                return collection_type(r)
            return r
        return new_func
    return collectify