bugfix for attempting to assing None to a list field
bugfix for attempting to assing None to a list field

NerdWallet/schematics,kstrauser/schematics,not-napoleon/schematics,nKey/schematics,promptworks/schematics,mlyundin/schematics,not-napoleon/schematics,promptworks/schematics,kstrauser/schematics,kaiix/schematics,eatfirst/schematics,ee08b397/schematics,ee08b397/schematics,openprocurement/schematics