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
tion value='koszko' selected='selected'>koszko</option>
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<div class='path'>path: <a href='/guix/log/?id=084e675ac884a27123e1198a08114d35f438f06e'>root</a>/<a href='/guix/log/po?id=084e675ac884a27123e1198a08114d35f438f06e'>po</a>/<a href='/guix/log/po/packages?id=084e675ac884a27123e1198a08114d35f438f06e'>packages</a>/<a href='/guix/log/po/packages/oc.po?id=084e675ac884a27123e1198a08114d35f438f06e'>oc.po</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/po/packages/oc.po?id=084e675ac884a27123e1198a08114d35f438f06e&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-10-17 22:10:25 +0200'>2021-10-17</span></td><td><a href='/guix/commit/po/packages/oc.po?id=15c91189cb61c579f4289047c79530cefe75215f'>nls: Update translations.</a></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2021-09-02 04:06:52 +0200'>2021-09-02</span></td><td><a href='/guix/commit/po/packages/oc.po?id=1ff2092a39dc5c7c7cd9b4a0ba4b59f92e738efc'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/it.po: New file.
* po/packages/LINGUAS: Add `it'.
* po/*/*.po: Update translations.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2021-08-04 14:49:53 +0200'>2021-08-04</span></td><td><a href='/guix/commit/po/packages/oc.po?id=6c10c96fedf707d7be059aeb79bd5c8e2d2fa210'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/doc/guix-cookbook.ru.po: New file.
* po/doc/guix-cookbook.sk.po: New file.
* po/*/*.po: Update translations.
* doc/local.mk (COOKBOOK_LANGUAGES): Add ru and sk.
(info_TEXINFOS): Add Russian and Slovak cookbooks.
* po/doc/local.mk (DOC_COOKBOOK_PO_FILES): Add Russian and Slovak po
files.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2021-05-10 22:27:53 -0400'>2021-05-10</span></td><td><a href='/guix/commit/po/packages/oc.po?id=63d26e81eea7be63caeb0eb7ca26ca1cf963ec97'>nls: New nl and oc translations for the 'packages' component.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/nl.po: New file.
* po/packages/oc.po: Likewise.
* po/packages/LINGUAS: Register them.
</span></span></td><td>Maxim Cournoyer</td></tr>