pytest mocking .count() and .find() functions of MongoReplicaSetClient object

I have a script called commons.py which contains some most commonly used functions.

In my main script, I am creating a mongo connection object:

db_ob = commons.db_connection()

db_connection returns a MongoReplicaSetClient connection object.

how to write test cases for my below function??

def check_entries():
    try:
        db_ob = commons.db_connection()
    except:
        print('Unable to connect to db!!')
        return False
    db_name = 'my_db_name'
    collection_name = 'my_collection_name'
    db_data = db_ob[db_name][collection_name].find()
    if db_data.count() == 0:
        print('No entries found in the collection!')
        return False
    return True

I can mock my db_connection function but I am having problem mocking the .count() and .find() functions.