code: def handle_401(self, response, repo, **kwargs):
          
          if response.status_code != requests.codes.unauthorized:
              return response
  
          auth_info = response.headers.get('www-authenticate', '')
  
          if 'bearer' not in auth_info.lower():
              return response
  
          self._token_cache[repo] = self._get_token(auth_info, repo)
  
          # Consume content and release the original connection
          # to allow our new request to reuse the same one.
          # This pattern was inspired by the source code of requests.auth.HTTPDigestAuth
          response.content
          response.close()
          retry_request = response.request.copy()
          extract_cookies_to_jar(retry_request._cookies, response.request, response.raw)
          retry_request.prepare_cookies(retry_request._cookies)
  
          self._set_header(retry_request, repo)
          retry_response = response.connection.send(retry_request, **kwargs)
          retry_response.history.append(response)
          retry_response.request = retry_request
  
          return retry_response
docs: Fetch Bearer token and retry.