"""Some util function for the app"""
import urlparse
import urllib

def update_url(url, params):
    """update params in the `url` query string"""
    url_parts = list(urlparse.urlparse(url))
    query = dict(urlparse.parse_qsl(url_parts[4]))
    query.update(params)
    url_parts[4] = urllib.urlencode(query)
    return urlparse.urlunparse(url_parts)