Use str.format for the demo

coolreader18 · coolreader18 · commit ab23f2c94018 · 2018-12-24T15:28:49.000-06:00
diff --git a/wasm/demo/src/index.html b/wasm/demo/src/index.html
@@ -19,7 +19,7 @@ <h1>RustPython Demo</h1>
 count = 0
 until = 10
 
-print("These are the first " + str(until) + " number in a Fibonacci sequence:")
+print("These are the first {} numbers in a Fibonacci sequence:".format(until))
 
 while count < until:
     print(n1)
