update README.md

Amberlan1001 · Amberlan1001 · commit 4a2138042dbc · 2020-09-03T09:38:45.000+08:00
diff --git a/README.md b/README.md
@@ -66,6 +66,6 @@ import tensorflow as tf
 tf.print("tensorflow version:",tf.__version__)
 ```
 
-```
+```python
 tensorflow version: 2.1.0
 ```
