def _make_path(self, items):
        '''Returns a relative path for the given dictionary of items.

        Uses this url rule's url pattern and replaces instances of <var_name>
        with the appropriate value from the items dict.
        '''
        for key, val in items.items():
            if not isinstance(val, basestring):
                raise TypeError, ('Value "%s" for key "%s" must be an instance'
                                  ' of basestring' % (val, key))
            items[key] = quote_plus(val)

        try:
            path = self._url_format.format(**items)
        except AttributeError:
            # Old version of python
            path = self._url_format
            for key, val in items.items():
                path = path.replace('{%s}' % key, val)
        return path
Returns a relative path for the given dictionary of items.

        Uses this url rule's url pattern and replaces instances of <var_name>
        with the appropriate value from the items dict.