Overwritten Django's reverse function which additionally allows to construct query string for an URL.

reverse_qs.py

def reverse_qs(*args, **kwargs):
    """Overwritten django reverse function which additionally allows
    to construct query string for an URL.

    New kwargs:
        * `params` a normal python dict.
        * `q_dict` a QueryDict instance.
        * `q_string` a query string same as in URL.

    Examples of usage:
        >>> reverse_qs('example', params={'id': 123, 'tags': ['a', 'b']})
        http://example.com?id=123&tags=a&tags=b

        >>> reverse_qs(
            viewname='example',
            q_dict=self.request.GET,  # <QueryDict: {'old': ['false']}>
            q_string='new=true',
        )
        http://example.com?new=true&old=false
    """
    params = kwargs.pop('params', {})
    q_dict = kwargs.pop('q_dict', None)
    q_string = kwargs.pop('q_string', '')

    query_dict = QueryDict('', mutable=True)

    if params:
        query_dict.update(_dict_to_query_dict(params))
    if q_dict:
        query_dict.update(q_dict)
    if q_string:
        query_dict.update(QueryDict(q_string))

    url = reverse(*args, **kwargs)

    if query_dict:
        query_string = query_dict.urlencode()
        return '{}?{}'.format(url, query_string)
    return url


def _dict_to_query_dict(params):
    """Converts python dict to django's QueryDict"""
    query_dict = QueryDict('', mutable=True)
    for key, value in params.iteritems():
        if value is None:
            query_dict[key] = ''
        elif isinstance(value, (int, long, float, basestring)):
            query_dict[key] = value
        elif isinstance(value, list):
            query_dict.setlist(key, value)
        else:
            raise ValueError
    return query_dict