code: def request_access_token(self, code, redirect_uri=None):
          '''
          Return access token as a JsonDict:
          {
              "access_token": "your-access-token",
              "expires": 12345678, # represented using standard unix-epoch-time
              "uid": 1234 # other fields
          }
          '''
          r = self._mixin.request_access_token(code, redirect_uri)
          self._access_token = r.access_token
          return f request_access_token(self, code, redirect_uri=None):
          '''
          Return access token as a JsonDict:
          {
              "access_token": "your-access-token",
              "expires": 12345678, # represented using standard unix-epoch-time
              "uid": 1234 # other fields
          }
          '''
          r = self._mixin.request_access_token(code, redirect_uri)
          self._access_token = r.access_token
          return r
docs: Return access token as a JsonDict:
          {
              "access_token": "your-access-token",
              "expires": 12345678, # represented using standard unix-epoch-time
              "uid": 1234 # other fields
          }