only admins can purge messages

app/dragon-bot.py

@@ -288,6 +288,11 @@ async def on_message(message):
         )
 
     if message.content.startswith('!purge'):
+        if not role_check.is_admin(message.author.roles):
+            return await client.send_message(
+                message.channel,
+                "You dont have permission to run docker commands"
+            )
         num = 20
         if len(message.content.split()) > 1:
             try: