How to use the gc3pie.gc3libs.url.Url function in gc3pie

def __new__(cls, urlstring=None, force_abs=True,
                scheme='file', netloc='', path='',
                hostname=None, port=None, username=None, password=None):
        """
        Create a new `Url` object.  See the `Url`:class: documentation
        for invocation syntax.
        """
        if urlstring is not None:
            if isinstance(urlstring, Url):
                # copy constructor
                return tuple.__new__(cls, (
                    urlstring.scheme, urlstring.netloc, urlstring.path,
                    urlstring.hostname, urlstring.port,
                    urlstring.username, urlstring.password,
                ))
            else:
                # parse `urlstring` and use kwd arguments as default values
                try:
                    urldata = urlparse.urlsplit(
                        urlstring, scheme=scheme, allow_fragments=False)
                    if urldata.scheme == 'file' and not os.path.isabs(
                            urldata.path) and force_abs:
                        urldata = urlparse.urlsplit(
                            'file://' + os.path.abspath(urldata.path))
                    return tuple.__new__(cls, (

>>> u2 = u1.adjoin('moredata')
            >>> str(u2)
            'http://www.example.org/data/moredata'

        Even if `relpath` starts with `/`, it is still appended to the
        path in the base URL::

            >>> u3 = u2.adjoin('/evenmore')
            >>> str(u3)
            'http://www.example.org/data/moredata/evenmore'

        """
        if relpath.startswith('/'):
            relpath = relpath[1:]
        return Url(scheme=self.scheme, netloc=self.netloc,
                   path=os.path.join((self.path or '/'), relpath),
                   hostname=self.hostname, port=self.port,
                   username=self.username, password=self.password)

def __setitem__(self, key, value):
        try:
            dict.__setitem__(self, Url(key, self._force_abs), value)
        except:
            dict.__setitem__(self, key, value)

>>> u == 'file:///tmp/foo'
          True
          >>> u == 'http://example.org'
          False

          >>> u == 42
          False

        """
        try:
            # The `tuple.__eq__` call can only be used if both `self`
            # and `other` are `tuple` subclasses; we know that `self`
            # is, but we need to check `other`.
            return ((isinstance(other, tuple) and tuple.__eq__(self, other))
                    or str(self) == str(other)
                    or tuple.__eq__(self, Url(other)))
        except ValueError:
            # `other` is not a URL and cannot be made into one
            return False

def __getitem__(self, key):
        try:
            return dict.__getitem__(self, key)
        except KeyError as ex:
            # map `key` to a URL and try with that
            try:
                return dict.__getitem__(self, Url(key, self._force_abs))
            except:
                raise ex

def __setitem__(self, key, value):
        try:
            dict.__setitem__(self, key, Url(value, self._force_abs))
        except:
            dict.__setitem__(self, key, value)