diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 6d20d09..9da9036 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -17,13 +17,9 @@ jobs:
     strategy:
       matrix:
         python-version:
-        - '3.7'
-        - '3.8'
         - '3.9'
         - '3.10'
         - '3.11.0-rc.1 - 3.11'
-        - 'pypy-3.7'
-        - 'pypy-3.8'
         - 'pypy-3.9'
         os-version:
         - 'ubuntu-latest'
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 9c5288b..3427477 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -16,6 +16,5 @@ twine; implementation_name=="cpython"
 types-beautifulsoup4
 types-python-dateutil
 types-requests
-backports.zoneinfo; python_version<"3.9"
 tzdata
 wheel
diff --git a/src/wwvb/tz.py b/src/wwvb/tz.py
index e6254e4..d1fb3b4 100644
--- a/src/wwvb/tz.py
+++ b/src/wwvb/tz.py
@@ -6,16 +6,7 @@
 #
 # SPDX-License-Identifier: GPL-3.0-only
 
-import datetime
-import sys
-from typing import Callable
-
-ZoneInfo: Callable[[str], datetime.tzinfo]
-
-if sys.version_info >= (3, 9):  # pragma no coverage
-    from zoneinfo import ZoneInfo
-else:  # pragma no coverage
-    from backports.zoneinfo import ZoneInfo
+from zoneinfo import ZoneInfo
 
 Mountain = ZoneInfo("America/Denver")