Pip module lockfile is required for Windows lock compat.

vladionescu · vladionescu · commit 8491495059b1 · 2016-05-25T15:12:02.000-07:00
diff --git a/requirements.txt b/requirements.txt
@@ -1 +1,2 @@
 setuptools>=20.3.1
+lockfile>=0.12.2
