code: def _get_session_cookies(session, access_token):
      
      headers = {'Authorization': 'Bearer {}'.format(access_token)}
  
      try:
          r = session.get(('https://accounts.google.com/accounts/OAuthLogin'
                           '?source=hangups&issueuberauth=1'), headers=headers)
          r.raise_for_status()
      except requests.RequestException as e:
          raise GoogleAuthError('OAuthLogin request failed: {}'.format(e))
      uberauth = r.text
  
      try:
          r = session.get(('https://accounts.google.com/MergeSession?'
                           'service=mail&'
                           'continue=http://www.google.com&uberauth={}')
                          .format(uberauth), headers=headers)
          r.raise_for_status()
      except requests.RequestException as e:
          raise GoogleAuthError('MergeSession request failed: {}'.format(e))
  
      cookies = session.cookies.get_dict(domain='.google.com')
      if cookies == {}:
          raise GoogleAuthError('Failed to find session cookies')
      return cookies
docs: Use the access token to get session cookies.
  
      Raises GoogleAuthError if session cookies could not be loaded.
  
      Returns dict of cookies.