diff --git a/src/privateer2/server.py b/src/privateer2/server.py
index 513e730..9d0febd 100644
--- a/src/privateer2/server.py
+++ b/src/privateer2/server.py
@@ -1,5 +1,3 @@
-from contextlib import contextmanager
-
 import docker
 from privateer2.keys import check
 from privateer2.util import (
diff --git a/tests/test_keys.py b/tests/test_keys.py
index b303f64..6119bbd 100644
--- a/tests/test_keys.py
+++ b/tests/test_keys.py
@@ -1,6 +1,4 @@
 from unittest.mock import MagicMock, call
-import os
-import platform
 
 import pytest
 import vault_dev
@@ -8,8 +6,14 @@
 import docker
 import privateer2.keys
 from privateer2.config import read_config
-from privateer2.keys import _check_connections, _keys_data, check, configure, keygen, keygen_all
-from privateer2.server import transient_server
+from privateer2.keys import (
+    _check_connections,
+    _keys_data,
+    check,
+    configure,
+    keygen,
+    keygen_all,
+)
 from privateer2.util import string_from_volume
 
 
@@ -158,7 +162,9 @@ def test_can_check_connections(capsys, monkeypatch, managed_docker):
         _check_connections(cfg, cfg.clients[0])
 
         out = capsys.readouterr().out
-        assert out == "checking connection to 'alice' (alice.example.com)...OK\n"
+        assert (
+            out == "checking connection to 'alice' (alice.example.com)...OK\n"
+        )
         assert mock_docker.from_env.called
         client = mock_docker.from_env.return_value
         mount = mock_docker.types.Mount
@@ -213,6 +219,7 @@ def test_can_report_connection_failure(capsys, monkeypatch, managed_docker):
             remove=True,
         )
 
+
 def test_only_test_connection_for_clients(monkeypatch, managed_docker):
     mock_check = MagicMock()
     monkeypatch.setattr(privateer2.keys, "_check_connections", mock_check)