diff --git a/pyproject.toml b/pyproject.toml
index a1feb4e..a86352e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -55,13 +55,15 @@ commands =
   {envpython} -X dev -bb -W error -m pytekukko.examples.print_collection_schedules --help
   {envpython} -X dev -bb -W error -m pytekukko.examples.print_invoice_headers --help
   {envpython} -X dev -bb -W error -m pytekukko.examples.print_next_collections --help
-  {envpython} -X dev -bb -W error -m pytekukko.examples.update_google_calendar --help
+  {envpython} -X dev -bb -W error {env:PYTEKUKKO_CERTIFI_IMPORTLIB_RESOURCES_PATH_W:} -m pytekukko.examples.update_google_calendar --help
 [testenv:py311]
 setenv =
   # https://github.com/aio-libs/aiohttp/issues/6600
   AIOHTTP_NO_EXTENSIONS = 1
   # https://github.com/aio-libs/yarl/issues/680
   YARL_NO_EXTENSIONS = 1
+  # https://github.com/certifi/python-certifi/issues/170#issuecomment-952885966
+  PYTEKUKKO_CERTIFI_IMPORTLIB_RESOURCES_PATH_W = -W "default:path is deprecated:DeprecationWarning:certifi.core"
 [testenv:pyston3]
 basepython = pyston3
 [gh-actions]