diff --git a/OpenSSL/test/test_crypto.py b/OpenSSL/test/test_crypto.py
index 5acd2b9..8b310dd 100644
--- a/OpenSSL/test/test_crypto.py
+++ b/OpenSSL/test/test_crypto.py
@@ -14,9 +14,7 @@
 from subprocess import PIPE, Popen
 from datetime import datetime, timedelta
 
-from six import u, b, binary_type, PY3
-from warnings import simplefilter
-from warnings import catch_warnings
+from six import u, b, binary_type
 
 from OpenSSL.crypto import TYPE_RSA, TYPE_DSA, Error, PKey, PKeyType
 from OpenSSL.crypto import X509, X509Type, X509Name, X509NameType