importer crash: NameError: global name 'maintainer_realname' is not defined

2018-11-27 +0000 10:23:14,980 DEBUG [debexpo.importer.24083] Importer started with arguments: ['-i', '/var/www/debexpo/live.ini', '-c', 'libhx_3.24-1_source.changes']
2018-11-27 +0000 10:23:14,983 DEBUG [debexpo.importer.24083] Determining user from 'Changed-By:' field: Jörg Frings-Fürst <debian@jff.email>
2018-11-27 +0000 10:23:14,984 DEBUG [debexpo.importer.24083] Changed-By's email address is: debian@jff.email
2018-11-27 +0000 10:23:15,152 DEBUG [debexpo.importer.24083] GPG signature matches user Jörg Frings-Fürst <debian@jff-webhosting.net>
Traceback (most recent call last):
  File "/var/www/debexpo/bin/debexpo_importer.py", line 667, in <module>
    main()
  File "/var/www/debexpo/bin/debexpo_importer.py", line 663, in main
    i.main()
  File "/var/www/debexpo/bin/debexpo_importer.py", line 449, in main
    self.user = User(id=-1, name=maintainer_realname, email=maintainer_email_address)
NameError: global name 'maintainer_realname' is not defined

2018-11-27 +0000 10:23:15,195 DEBUG [debexpo.worker] Remove stale file /var/cache/debexpo/incoming/libhx_3.24-1.dsc - the importer probably crashed
2018-11-27 +0000 10:23:15,195 DEBUG [debexpo.worker] Remove stale file /var/cache/debexpo/incoming/libhx_3.24.orig.tar.xz - the importer probably crashed
2018-11-27 +0000 10:23:15,196 DEBUG [debexpo.worker] Remove stale file /var/cache/debexpo/incoming/libhx_3.24-1.debian.tar.xz - the importer probably crashed
2018-11-27 +0000 10:23:15,196 DEBUG [debexpo.worker] Remove stale file /var/cache/debexpo/incoming/libhx_3.24-1_source.buildinfo - the importer probably crashed
2018-11-27 +0000 10:23:15,196 DEBUG [debexpo.worker] Remove stale file /var/cache/debexpo/incoming/libhx_3.24-1_source.changes - the importer probably crashed
2018-11-27 +0000 10:23:15,196 DEBUG [debexpo.worker] Job importuploads complete