Using Airflow custom operator with Bitnami helm chart

Question

I have deployed Airflow on Minikube using the Bitnami helm chart based on this. I have used Git sync to sync Dag files and plugin files like this. But when the Airflow pipeline was installed with helm, it can not import operators from plugins.

The structure of the plugins folder is like this:

plugins
├── dag_builder.py
└── operators
    ├── hello_operator.py
    ├── mysql_to_s3.py
    └── postgres_to_s3.py

In the dag file, I have imported the operator:

from operators.mysql_to_s3 import MySQLToS3ParquetOperator

err: No module named 'operators

How should I import custom operators here? It works when using docker-compose, but when using Bitnami Helm Chart it doesn't.