docs: def _join_url(self, base, url, admin_forwarder=False):
          """
          overrides `urlparse.urljoin` since it removes base url path
          https://docs.python.org/2/library/urlparse.html#urlparse.urljoin
          """
          if admin_forwarder:
              return base + url
          else:
              return urljoin(base, url)