Update main.dart

Indumathi1195R · web-flow · commit 29ee15a7ed58 · 2021-05-06T12:07:35.000+05:30
Sample updated.
diff --git a/lib/main.dart b/lib/main.dart
@@ -1,3 +1,4 @@
+// @dart=2.9
 library event_calendar;
 
 import 'dart:math';
