diff --git a/tox.ini b/tox.ini
index 74ea1d4..6ae707b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,7 +8,7 @@ envlist=
 combine_as_imports=True
 force_sort_within_sections=True
 include_trailing_comma=True
-known_standard_library=pytest
+known_third_party=hypothesis,pytest
 known_first_party=<MODULE_NAME>
 line_length=21
 multi_line_output=3