diff --git a/requirements_dev.txt b/requirements_dev.txt
index 6f60faa..ea58bfb 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -1,14 +1,13 @@
+bump2version
+coverage==4.5.2
+flake8==3.6.0
+mock==2.0.0
 pip==18.1
-bumpversion==0.5.3
-wheel==0.32.3
-watchdog==0.9.0
-flake8==3.6.0
-tox==3.6.1
-coverage==4.5.2
+pytest==4.0.2
+pytest-runner==4.2
 six==1.12.0
 Sphinx==1.8.3
+tox==3.6.1
 twine==1.12.1
-
-mock==2.0.0
-pytest==4.0.2
-pytest-runner==4.2
+watchdog==0.9.0
+wheel==0.32.3