diff --git a/test-requirements.txt b/test-requirements.txt
index 59308a85..a2619fa6 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -3,7 +3,7 @@ flake8==3.7.9
 mccabe==0.6.1
 mock>=3.0.5, <4.0.2
 pycodestyle==2.5.0
-pyfakefs >= 3.6, < 4.0
+pyfakefs>=3.6, <4.1
 pyflakes==2.1.1
 pytest >= 5.0.1, < 6.0.0
 pytest-cov >= 2.7.1, < 3.0.0