Comment 2 for bug 2019864

I am aware, I have found the part that seems interesting:

dpkg-buildpackage
-----------------

Command: dpkg-buildpackage -us -uc -mLaunchpad Build Daemon <email address hidden> -b -rfakeroot
dpkg-buildpackage: info: source package simplestreams
dpkg-buildpackage: info: source version 0.1.0~bzr460-0ubuntu1.2~ppa1
dpkg-buildpackage: info: source distribution bionic
 dpkg-source --before-build simplestreams-0.1.0~bzr460
dpkg-buildpackage: info: host architecture amd64
 fakeroot debian/rules clean
dh clean --with=python2,python3
dh: Compatibility levels before 9 are deprecated (level 7 in use)
   dh_auto_clean
dh_auto_clean: Compatibility levels before 9 are deprecated (level 7 in use)
   dh_clean
dh_clean: Compatibility levels before 9 are deprecated (level 7 in use)
 debian/rules build
dh build --with=python2,python3
dh: Compatibility levels before 9 are deprecated (level 7 in use)
   dh_update_autotools_config
   dh_auto_configure
dh_auto_configure: Compatibility levels before 9 are deprecated (level 7 in use)
   dh_auto_build
dh_auto_build: Compatibility levels before 9 are deprecated (level 7 in use)
 make -j1
make[1]: Entering directory '/<<PKGBUILDDIR>>'
nothing to do for build
make[1]: Leaving directory '/<<PKGBUILDDIR>>'
   dh_auto_test
dh_auto_test: Compatibility levels before 9 are deprecated (level 7 in use)
 make -j1 test
make[1]: Entering directory '/<<PKGBUILDDIR>>'
./tools/create-gpgdir
creating GNUPGHOME dir in /<<PKGBUILDDIR>>/gnupg.
  pubkey '/<<PKGBUILDDIR>>/examples/keys/example.pub'
  secret '/<<PKGBUILDDIR>>/examples/keys/example.sec'
  pubkeys: /<<PKGBUILDDIR>>/examples/keys/example.pub
imported secret key /<<PKGBUILDDIR>>/examples/keys/example.sec
imported pubkey /<<PKGBUILDDIR>>/examples/keys/example.pub
./tools/tenv ./tools/sign-examples
Traceback (most recent call last):
  File "/<<PKGBUILDDIR>>/tools/js2signed", line 53, in <module>
    main()
  File "/<<PKGBUILDDIR>>/tools/js2signed", line 41, in main
    signjson_file(path, force=force)
  File "/<<PKGBUILDDIR>>/tools/sign_helper.py", line 25, in signjson_file
    util.sign_file(fname, inline=False)
  File "/<<PKGBUILDDIR>>/simplestreams/util.py", line 546, in sign_file
    return subp(get_sign_cmd(path=fname, output=outfile, inline=inline))[0]
  File "/<<PKGBUILDDIR>>/simplestreams/util.py", line 458, in subp
    raise subprocess.CalledProcessError(rc, args, output=(out, err))
subprocess.CalledProcessError: Command '['gpg', '--batch', '--output', '/<<PKGBUILDDIR>>/examples/cirros/streams/v1/index.json.gpg', '--armor', '--detach-sign', '/<<PKGBUILDDIR>>/examples/cirros/streams/v1/index.json']' returned non-zero exit status 2
Makefile:39: recipe for target 'examples-sign' failed
make[1]: *** [examples-sign] Error 1
make[1]: Leaving directory '/<<PKGBUILDDIR>>'
dh_auto_test: make -j1 test returned exit code 2
debian/rules:7: recipe for target 'build' failed
make: *** [build] Error 2
dpkg-buildpackage: error: debian/rules build subprocess returned exit status 2
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Build finished at 2023-05-16T14:04:28Z