pyflix: add passing event name to off method

tools/pyflix/README.md

@@ -59,6 +59,13 @@ flix.on('disconnected', lambda: print('Disconnected from Flix'))
 flix.on('print', lambda text: print(f'Flix says: {text}'))
 ```
 
+Unsubscribe from events using `off` method:
+
+```python
+flix.off('print')  # unsubscribe from print events
+flix.off(callback)  # unsubscribe specific callback
+```
+
 You can also wait for specific events using `wait` method. This method returns the data associated with the event:
 
 ```python

tools/pyflix/flix.py

@@ -87,10 +87,15 @@ class Flix:
             self._event_listeners[event] = []
         self._event_listeners[event].append(callback)
 
-    def off(self, callback: Callable):
+    def off(self, event_or_callback: Union[str, Callable]):
-        for event in self._event_listeners:
+        if isinstance(event_or_callback, str):
-            if callback in self._event_listeners[event]:
+            event = event_or_callback.lower()
-                self._event_listeners[event].remove(callback)
+            if event in self._event_listeners:
+                del self._event_listeners[event]
+        else:
+            for event in self._event_listeners:
+                if event_or_callback in self._event_listeners[event]:
+                    self._event_listeners[event].remove(event_or_callback)
 
     def _trigger(self, event: str, *args):
         event = event.lower()