update CHANGELOG.md

Author: KoyanagiHitoshi

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Change Log
 
+## [v1.7.0](https://github.com/KoyanagiHitoshi/AtCoder-Python-Introduction/releases/tag/v1.7.0) / 2022-07-03
+
+* [#7](https://github.com/KoyanagiHitoshi/AtCoder-Python-Introduction/pull/7) update CHANGELOG.md
+* [#7](https://github.com/KoyanagiHitoshi/AtCoder-Python-Introduction/pull/7) add code
+
 ## [v1.6.0](https://github.com/KoyanagiHitoshi/AtCoder-Python-Introduction/releases/tag/v1.6.0) / 2022-06-05
 
 * [#6](https://github.com/KoyanagiHitoshi/AtCoder-Python-Introduction/pull/6) update CHANGELOG.md