From fb06d12d5a32581ae531fc26143c14ac6c8ea8fe Mon Sep 17 00:00:00 2001
From: Paul Moore <p.f.moore@gmail.com>
Date: Tue, 17 Oct 2023 11:04:34 +0100
Subject: [PATCH] Handle ISO formats with a trailing Z

---
 news/12338.bugfix.rst                    |  1 +
 src/pip/_internal/self_outdated_check.py | 11 ++++++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)
 create mode 100644 news/12338.bugfix.rst

diff --git a/news/12338.bugfix.rst b/news/12338.bugfix.rst
new file mode 100644
index 00000000000..cd9a8c10baa
--- /dev/null
+++ b/news/12338.bugfix.rst
@@ -0,0 +1 @@
+Handle a timezone indicator of Z when parsing dates in the self check.
diff --git a/src/pip/_internal/self_outdated_check.py b/src/pip/_internal/self_outdated_check.py
index cb18edbed8e..0f64ae0e614 100644
--- a/src/pip/_internal/self_outdated_check.py
+++ b/src/pip/_internal/self_outdated_check.py
@@ -39,6 +39,15 @@ def _get_statefile_name(key: str) -> str:
     return name
 
 
+def _convert_date(isodate: str) -> datetime.datetime:
+    """Convert an ISO format string to a date.
+
+    Handles the format 2020-01-22T14:24:01Z (trailing Z)
+    which is not supported by older versions of fromisoformat.
+    """
+    return datetime.datetime.fromisoformat(isodate.replace("Z", "+00:00"))
+
+
 class SelfCheckState:
     def __init__(self, cache_dir: str) -> None:
         self._state: Dict[str, Any] = {}
@@ -73,7 +82,7 @@ def get(self, current_time: datetime.datetime) -> Optional[str]:
             return None
 
         # Determine if we need to refresh the state
-        last_check = datetime.datetime.fromisoformat(self._state["last_check"])
+        last_check = _convert_date(self._state["last_check"])
         time_since_last_check = current_time - last_check
         if time_since_last_check > _WEEK:
             return None