except Exception, ex: ^ SyntaxError: invalid syntax

Question

I am trying to run a flask socketio example, but don't understand this error :

C:\Users\alotfi
λ python -V
  Python 2.7.7

C:\Users\alotfi
λ cd C:\Users\alotfi\PycharmProjects\websocketSliders

C:\Users\alotfi\PycharmProjects\websocketSliders
λ env2\Scripts\activate
(env2) C:\Users\alotfi\PycharmProjects\websocketSliders
λ python app.py
Traceback (most recent call last):
 File "app.py", line 2, in <module>
 from flask.ext.socketio import SocketIO, emit
File "<frozen importlib._bootstrap>", line 1567, in _find_and_load
File "<frozen importlib._bootstrap>", line 1534, in _find_and_load_unlocked
File "C:\Users\alotfi\PycharmProjects\websocketSliders\env2\lib\site-  packages\flask\exthook.py", line 62, in load_module
  __import__(realname)
 File "C:\Users\alotfi\PycharmProjects\websocketSliders\env2\lib\site-  packages\flask_socketio\__init__.py", line 1, in <module>
from gevent import monkey
File "C:\Users\alotfi\PycharmProjects\websocketSliders\env2\lib\site-packages\gevent\__init__.py", line 36, in <module>
from gevent.hub import get_hub, iwait, wait
File "C:\Users\alotfi\PycharmProjects\websocketSliders\env2\lib\site- packages\gevent\hub.py", line 282
except Exception, ex:
                ^

SyntaxError: invalid syntax

Thanks.