Problem reported upstream:
https://github.com/linsomniac/python-memcached/issues/176

---
 memcache.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/memcache.py b/memcache.py
index 05b6657..b935681 100644
--- a/memcache.py
+++ b/memcache.py
@@ -1300,8 +1300,8 @@ class Client(threading.local):
             key = key[1]
         if key is None:
             raise Client.MemcachedKeyNoneError("Key is None")
-        if key is '':
-            if key_extra_len is 0:
+        if key == '':
+            if key_extra_len == 0:
                 raise Client.MemcachedKeyNoneError("Key is empty")

             #  key is empty but there is some other component to key
--
2.26.2
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<tr><td><span title='2022-12-10 11:24:07 +0100'>2022-12-10</span></td><td><a href='/guix/commit/gnu/installer/parted.scm?id=4473be9858b3575c1b3f2b67c135ac822136dde0'>installer: Detect mapped installation devices.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes: &lt;https://issues.guix.gnu.org/59823&gt;

* gnu/installer/parted.scm (mapped-device?,
mapped-device-parent-partition): New procedures.
(eligible-devices): Detect mapped installation devices using the new
procedures.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2022-10-31 09:34:13 +0100'>2022-10-31</span></td><td><a href='/guix/commit/gnu/installer/parted.scm?id=ab974ed709976d34917c8f6f9e5cc0004547af45'>installer: parted: Retry failing read-partition-uuid call.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes: &lt;https://issues.guix.gnu.org/53541&gt;.

* gnu/installer/parted.scm (read-partition-uuid/retry): New procedure.
(check-user-partitions): Use it.
</span></span></td><td>Mathieu Othacehe</td></tr>