from django_fast_export.csv import StreamingCSVResponse

response = StreamingCSVResponse.from_queryset(queryset)

from django_fast_export.csv import StreamingCSVResponse, all_values, all_verbose_names

def generate():
    yield (all_verbose_names(queryset.model) + ["Lösungen"])
    yield from (
        (all_values(instance) + [instance.get_solutions()]) for instance in queryset
    )

response = StreamingCSVResponse(generate())