def url_fix(s, charset='utf-8'):
    r"""Sometimes you get an URL by a user that just isn't a real URL because
    it contains unsafe characters like ' ' and so on.  This function can fix
    some of the problems in a similar way browsers handle data entered by the
    user:

    >>> url_fix(u'http://de.wikipedia.org/wiki/Elf (Begriffskl\xe4rung)')
    'http://de.wikipedia.org/wiki/Elf%20%28Begriffskl%C3%A4rung%29'

    :param s: the string with the URL to fix.
    :param charset: The target charset for the URL if the url was given as
                    unicode string.
    """
    if isinstance(s, unicode):
        s = s.encode(charset, 'replace')
    scheme, netloc, path, qs, anchor = _safe_urlsplit(s)
    path = _quote(path, '/%')
    qs = _quote_plus(qs, ':&%=')
    return urlparse.urlunsplit((scheme, netloc, path, qs, anchor))