The query adds dummy filter which gives 0 results

[apohllo]

in milvus.py there's a line 493 and following:

if filters is not None:
            filters += " and " + EMPTY_FIELD + " in [0]"
        else:
            filters = EMPTY_FIELD + " in [0]"

I don't know why the empty field is "required". Yet with a query that does not have any filters, the result is empty.
Changing filters to None gives non empty result