create python venv when needed

app.py

@@ -8,7 +8,7 @@ vars = {}
 
 logging.basicConfig(
     format="%(asctime)s %(message)s",
-    level=logging.INFO,
+    level=logging.INFO
 )
 
 async def handshake(ws,data):

entrypoint.sh

@@ -3,7 +3,11 @@
 BASE=$(dirname $0)
 cd $BASE
 git pull
-python3 -m venv env
+if [ -d env ];
+then
+    python3 -m venv env
+fi
+
 source env/bin/activate
 pip3 install -U -r requirements.txt
 exec python3 app.py