Use alert() for the WASM example crate

Author: coolreader18

wasm/example/src/main.py

@@ -1,13 +1,12 @@
-from browser import fetch
+from browser import fetch, alert
 
 def fetch_handler(repos):
     star_sum = 0
     for repo in repos:
         star_sum += repo['stars']
-    print(f'Average github trending star count: {star_sum / len(repos)}')
-
+    alert(f'Average github trending star count: {star_sum / len(repos)}')
 
 fetch(
     'https://github-trending-api.now.sh/repositories',
     response_format='json',
-).then(fetch_handler)
+).then(fetch_handler, lambda err: alert(f"Error: {err}"))