--- a/setup.cfg	2018-12-27 20:35:11.000000000 +0100
+++ b/setup.cfg	2019-01-02 10:19:34.658391238 +0100
@@ -57,7 +57,7 @@ setup_requires =
 	setuptools_scm>=1.15.0
 	setuptools_scm_git_archive>=1.0
 install_requires = 
-	backports.functools_lru_cache
+	backports.functools_lru_cache; python_version<"3.4.0"
 	six>=1.11.0
 	more_itertools>=2.6