diff --git a/tests/test_tree.py b/tests/test_tree.py
index 0b42fa7..df828ad 100644
--- a/tests/test_tree.py
+++ b/tests/test_tree.py
@@ -3,11 +3,10 @@
 import textwrap
 from decimal import Decimal
 from email.utils import format_datetime
-from http import HTTPStatus
 from unittest import TestCase
 
-import dateutil
 import requests_mock
+from dateutil.tz import tzoffset
 
 from tests.helpers import gzip
 from usp.log import create_logger
@@ -43,7 +42,7 @@ class TestSitemapTree(TestCase):
     # Publication / "last modified" date
     TEST_DATE_DATETIME = datetime.datetime(
         year=2009, month=12, day=17, hour=12, minute=4, second=56,
-        tzinfo=dateutil.tz.tzoffset(None, 7200),
+        tzinfo=tzoffset(None, 7200),
     )
     TEST_DATE_STR_ISO8601 = TEST_DATE_DATETIME.isoformat()
     """Test string date formatted as ISO 8601 (for XML and Atom 0.3 / 1.0 sitemaps)."""
@@ -59,8 +58,8 @@ def fallback_to_404_not_found_matcher(request):
         """Reply with "404 Not Found" to unmatched URLs instead of throwing NoMockAddress."""
         return requests_mock.create_response(
             request,
-            status_code=HTTPStatus.NOT_FOUND.value,
-            reason=HTTPStatus.NOT_FOUND.phrase,
+            status_code=404,
+            reason='Not Found',
             headers={'Content-Type': 'text/html'},
             text="<h1>404 Not Found!</h1>",
         )
@@ -276,8 +275,8 @@ def test_sitemap_tree_for_homepage(self):
             # Nonexistent sitemap
             m.get(
                 self.TEST_BASE_URL + '/sitemap_news_missing.xml',
-                status_code=HTTPStatus.NOT_FOUND.value,
-                reason=HTTPStatus.NOT_FOUND.phrase,
+                status_code=404,
+                reason='Not Found',
                 headers={'Content-Type': 'text/html'},
                 text="<h1>404 Not Found!</h1>",
             )
@@ -1177,8 +1176,8 @@ def test_sitemap_tree_for_homepage_no_robots_txt(self):
             # Nonexistent robots.txt
             m.get(
                 self.TEST_BASE_URL + '/robots.txt',
-                status_code=HTTPStatus.NOT_FOUND.value,
-                reason=HTTPStatus.NOT_FOUND.phrase,
+                status_code=404,
+                reason='Not Found',
                 headers={'Content-Type': 'text/html'},
                 text="<h1>404 Not Found!</h1>",
             )
diff --git a/usp/web_client/abstract_client.py b/usp/web_client/abstract_client.py
index 505d7ea..bcb06ef 100644
--- a/usp/web_client/abstract_client.py
+++ b/usp/web_client/abstract_client.py
@@ -7,25 +7,25 @@
 RETRYABLE_HTTP_STATUS_CODES = {
 
     # Some servers return "400 Bad Request" initially but upon retry start working again, no idea why
-    HTTPStatus.BAD_REQUEST.value,
+    int(HTTPStatus.BAD_REQUEST),
 
     # If we timed out requesting stuff, we can just try again
-    HTTPStatus.REQUEST_TIMEOUT.value,
+    int(HTTPStatus.REQUEST_TIMEOUT),
 
     # If we got rate limited, it makes sense to wait a bit
-    HTTPStatus.TOO_MANY_REQUESTS.value,
+    int(HTTPStatus.TOO_MANY_REQUESTS),
 
     # Server might be just fine on a subsequent attempt
-    HTTPStatus.INTERNAL_SERVER_ERROR.value,
+    int(HTTPStatus.INTERNAL_SERVER_ERROR),
 
     # Upstream might reappear on a retry
-    HTTPStatus.BAD_GATEWAY.value,
+    int(HTTPStatus.BAD_GATEWAY),
 
     # Service might become available again on a retry
-    HTTPStatus.SERVICE_UNAVAILABLE.value,
+    int(HTTPStatus.SERVICE_UNAVAILABLE),
 
     # Upstream might reappear on a retry
-    HTTPStatus.GATEWAY_TIMEOUT.value,
+    int(HTTPStatus.GATEWAY_TIMEOUT),
 
     # (unofficial) 509 Bandwidth Limit Exceeded (Apache Web Server/cPanel)
     509,