def sqla_uri_from_config_section(config_section) -> str:
    """
    >>> from jasmine.etl.app_base import sqla_uri_from_config_section
    >>> sqla_uri_from_config_section({
    ...     "uri": "mysq://blah:blah@blah/{username}={user}, {password}={pass}, {database}={db}",
    ...     "username": "username",
    ...     "password": "password",
    ...     "host": "localhost",
    ...     "database": "database",
    ... })
    'mysq://blah:blah@blah/username=username, password=password, database=database'
    >>> sqla_uri_from_config_section({
    ...     "username": "my_app_prod_ro",
    ...     "password": "my_ap_prod_ro_pass",
    ...     "host": "db_endpoint",
    ...     "database": "database",
    ... })
    'mysql+pymysql://my_app_prod_ro:my_ap_prod_ro_pass@db_endpoint:3306/database'
    """
    uri = config_section.get(
        "uri", "mysql+pymysql://{username}:{password}@{host}:{port}/{database}"
    )
    username = config_section.get("username", config_section.get("user", ""))
    password = config_section.get("password", config_section.get("pass", ""))
    host = config_section.get("host", "")
    port = config_section.get("port", "3306")
    database = config_section.get("database", config_section.get("db", ""))

    return uri.format(
        **{
            "username": username,
            "user": username,
            "password": password,
            "pass": password,
            "host": host,
            "port": port,
            "database": database,
            "db": database,
        }
    )