Slow down mail tasks some more to ensure they actually complete.
ApplicationError 1 might occur when mails are being sent too fast.
from django.core.management.base import AppCommand, CommandError
class Command(AppCommand):
help = "RENAMED: see 'sqlcustom'"
def handle(self, *apps, **options):
raise CommandError("This command has been renamed. Use the 'sqlcustom' command instead.")