update dependency

setup.py

@@ -143,7 +143,7 @@ setup_args = dict(
 
 setup_args['install_requires'] = [
     'ipython',
-    'setuptools',
+    'packaging',
     'tornado!=6.0.0, !=6.0.1, !=6.0.2',
     'jupyterlab_server~=2.0.0b8',
     'jupyter_server~=1.0.0rc16',