Used by Variable/Connection.

https://github.com/apache/airflow/blob/894741e311ffd642e036b80d3b1b5d53c3747cad/airflow/secrets/metastore.py#L32

"""Enum of encoding constants."""
    TYPE = "__type"
    VAR = "__var"
@unique
class DagAttributeTypes(str, Enum):
    """Enum of supported attribute types of DAG."""
    DAG = "dag"
    OP = "operator"
    DATETIME = "datetime"
    TIMEDELTA = "timedelta"
    TIMEZONE = "timezone"
    RELATIVEDELTA = "relativedelta"
    DICT = "dict"
    SET = "set"
    TUPLE = "tuple"
    POD = "k8s.V1Pod"
    TASK_GROUP = "taskgroup"
    EDGE_INFO = "edgeinfo"
    PARAM = "param"
    XCOM_REF = "xcomref"
    DATASET = "dataset"
    SIMPLE_TASK_INSTANCE = "simple_task_instance"
    BASE_JOB = "Job"
    TASK_INSTANCE = "task_instance"
    DAG_RUN = "dag_run"
    DATA_SET = "data_set"
    ARG_NOT_SET = "arg_not_set"