code: def get_redirect_url(self, state='', **kwargs):
          
          params = {
              'response_type': 'code',
              'client_id': self.client_id,
              'redirect_uri': self.get_callback_url(**kwargs),
              'scope': self.scope or '',
              'state': state,
          }
          
          return '%s?%s' % (self.auth_url, urllib.urlencode(params))
docs: Assemble the URL to where we'll be redirecting the user to to request
          permissions.