code: def url(self, **urlargs):
          '''Build a ``url`` from ``urlargs`` key-value parameters
          '''
          if self.defaults:
              d = self.defaults.copy()
              d.update(urlargs)
              urlargs = d
          url = '/'.join(self._url_generator(urlargs))
          if not url:
              return '/'
          else:
              url = '/' + url
              return url if self.is_leaf else url + '/f url(self, **urlargs):
          '''Build a ``url`` from ``urlargs`` key-value parameters
          '''
          if self.defaults:
              d = self.defaults.copy()
              d.update(urlargs)
              urlargs = d
          url = '/'.join(self._url_generator(urlargs))
          if not url:
              return '/'
          else:
              url = '/' + url
              return url if self.is_leaf else url + '/'
docs: Build a ``url`` from ``urlargs`` key-value parameters