explain the sleep

bigtext.py

@@ -26,14 +26,16 @@ import threading
 
 
 class FileObserver(FileSystemEventHandler):
-    counter = 0
+
     def __init__(self, big_text):
         super(FileObserver, self).__init__()
         self.big_text = big_text
 
     def on_modified(self, event):
-        #print("file modified ", self.counter," ", time.time())
-        self.counter+=1
+        # slow down the updates. This is needed, because the file is modified
+        # constantly, which would lead to constant re-rendering, which would
+        # block the UI thread an make the UI unresponsive.
+        # Note: we don't miss events, because they are queued and de-duplicated
         time.sleep(0.5)
         self.big_text.update()