See suggestion in https://github.com/bskinn/sphobjinv/issues/275

This prevents the module from creating an ssl context upon import, when,
during a build especially, a certificate file may not be present.  Otherwise
module import would fail.

--- a/src/sphobjinv/inventory.py
+++ b/src/sphobjinv/inventory.py
@@ -30,7 +30,6 @@ Sphinx |objects.inv| files.
 """
 
 import re
-import ssl
 import urllib.request as urlrq
 from zlib import error as zlib_error
 
@@ -218,8 +217,15 @@ class Inventory:
     #: zlib compression line for v2 |objects.inv| header
     header_zlib = "# The remainder of this file is compressed using zlib."
 
-    # Private class member for SSL context, since context creation is slow(?)
-    _sslcontext = ssl.create_default_context(cafile=certifi.where())
+    # Private class member for SSL context
+    _sslcontext_ = None
+
+    @property
+    def _sslcontext(self):
+        import ssl
+        if not self._sslcontext_:
+            self._sslcontext_ = ssl.create_default_context(cafile=certifi.where())
+        return self._sslcontext_
 
     @property
     def count(self):
f86a00b3d13d6fff262a5ad'>refs</a><a class='active' href='/guix/log/gnu/services/auditd.scm'>log</a><a href='/guix/tree/gnu/services/auditd.scm?id=50901dcb23fff7ba4f86a00b3d13d6fff262a5ad'>tree</a><a href='/guix/commit/gnu/services/auditd.scm?id=50901dcb23fff7ba4f86a00b3d13d6fff262a5ad'>commit</a><a href='/guix/diff/gnu/services/auditd.scm?id=50901dcb23fff7ba4f86a00b3d13d6fff262a5ad'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/services/auditd.scm'>
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<div class='path'>path: <a href='/guix/log/?id=50901dcb23fff7ba4f86a00b3d13d6fff262a5ad'>root</a>/<a href='/guix/log/gnu?id=50901dcb23fff7ba4f86a00b3d13d6fff262a5ad'>gnu</a>/<a href='/guix/log/gnu/services?id=50901dcb23fff7ba4f86a00b3d13d6fff262a5ad'>services</a>/<a href='/guix/log/gnu/services/auditd.scm?id=50901dcb23fff7ba4f86a00b3d13d6fff262a5ad'>auditd.scm</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/gnu/services/auditd.scm?id=50901dcb23fff7ba4f86a00b3d13d6fff262a5ad&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-11-30 01:08:55 +0100'>2021-11-30</span></td><td><a href='/guix/commit/gnu/services/auditd.scm?id=892f1b7273d57b25940700877a02618fe826cc08'>services: Accept &lt;inferior-package&gt;s in lieu of &lt;package&gt;s.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/authentication.scm (fprintd-configuration)
(nslcd-configuration): Substitute file-like objects for package ones.
* gnu/services/cgit.scm (cgit-configuration, opaque-cgit-configuration):
Likewise.
* gnu/services/cups.scm (package-list?, cups-configuration): Likewise.
* gnu/services/dns.scm (verify-knot-configuration)
(ddclient-configuration): Likewise.
* gnu/services/docker.scm (docker-configuration): Likewise.
* gnu/services/file-sharing.scm (transmission-daemon-configuration): Likewise.
* gnu/services/getmail.scm (getmail-configuration): Likewise.
* gnu/services/mail.scm (dovecot-configuration)
(opaque-dovecot-configuration): Likewise.
* gnu/services/messaging.scm (prosody-configuration)
(opaque-prosody-configuration): Likewise.
* gnu/services/monitoring.scm (zabbix-server-configuration)
(zabbix-agent-configuration): Likewise.
* gnu/services/networking.scm (opendht-configuration): Likewise.
* gnu/services/pm.scm (tlp-configuration): Likewise.
* gnu/services/telephony.scm (jami-configuration): Likewise.
* gnu/services/virtualization.scm (libvirt-configuration)
(qemu-guest-agent-configuration): Likewise.
* gnu/services/vpn.scm (openvpn-client-configuration): Likewise.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-07-27 12:06:36 +0200'>2020-07-27</span></td><td><a href='/guix/commit/gnu/services/auditd.scm?id=73cb3e103f35356b83cb091f15c536c21bf53981'>services: auditd: Provide default configuration directory.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/auditd.scm (auditd.conf)
(%default-auditd-configuration-directory): New variables.
(&lt;auditd-configuration&gt;): Switch to 'define-record-type*'.
[configuration-directory]: New field.
(auditd-shepherd-service): Honor 'configuration-directory'.  Pass #:pid-file.
(auditd-service-type)[description]: Tweak.
[default-value]: Provide 'configuration-directory'.
* doc/guix.texi (Miscellaneous Services): Update docs to reflect
changes.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Robin Green</td></tr>