When calling get_families, you receiving exception
When calling get_families, you receiving exception "'FamilyElement' object has no attribute 'is_family'"

To Reproduce
Steps to reproduce the behavior: (Example)

1. Download attached gedcom_bug_report.py.txt
2. Rename gedcom_bug_report.py.txt to gedcom_bug_report.py
3. Download attached korets_one_person.ged.txt
4. Rename korets_one_person.ged.txt to korets_one_person.ged
5. Put latest gedcom folder, to same folder
6. Run gedcom_bug_report.py
7. See error "'FamilyElement' object has no attribute 'is_family'"

Expected behavior
Return all families without errors

Version
Latest source version (not pip version)

gedcom_bug_report.py.txt
korets_one_person.ged.txt