diff --git a/FluentPython/17-futures-py3.7/countries/requirements.txt b/FluentPython/17-futures-py3.7/countries/requirements.txt
index aa7a6de..bebeee3 100644
--- a/FluentPython/17-futures-py3.7/countries/requirements.txt
+++ b/FluentPython/17-futures-py3.7/countries/requirements.txt
@@ -1,2 +1,2 @@
 requests==2.21.0
-aiohttp==3.5.4
+aiohttp==3.7.4