diff --git a/.isort.cfg b/.isort.cfg
index d9eb4010..dfa946d0 100644
--- a/.isort.cfg
+++ b/.isort.cfg
@@ -1,5 +1,5 @@
 [settings]
-known_third_party=cybox,lxml,maec,netaddr,pycountry,pytest,six,stix,stix2,stix2validator,stixmarx
+known_third_party=cybox,lxml,maec,netaddr,pycountry,pytest,stix,stix2,stix2validator,stixmarx
 known_first_party=stix2elevator
 force_sort_within_sections=1
 multi_line_output=5
diff --git a/stix2elevator/test/test_idioms.py b/stix2elevator/test/test_idioms.py
index 20dcc37e..ebbd6a95 100644
--- a/stix2elevator/test/test_idioms.py
+++ b/stix2elevator/test/test_idioms.py
@@ -6,9 +6,6 @@
 import os
 import sys
 
-# external
-from six.moves import zip
-
 # internal
 from stix2elevator import elevate
 from stix2elevator.options import (