[enh] add decorator to always relaunch a function

schedule.py

@@ -0,0 +1,21 @@
+import asyncio
+from functools import wraps
+
+
+def always_relaunch(sleep):
+    def decorator(function):
+        @wraps(function)
+        async def wrap(*args, **kwargs):
+            while True:
+                try:
+                    await function(*args, **kwargs)
+                except KeyboardInterrupt:
+                    return
+                except Exception as e:
+                    import traceback
+                    traceback.print_exc()
+                    print(f"Error: exception in function '{function.__name__}', relaunch in {sleep} seconds")
+                finally:
+                    await asyncio.sleep(sleep)
+        return wrap
+    return decorator