How to use the bigflow.core.entity.EntitiedBySelf function in bigflow

Note:   [int] means a list of ints, it can accept any number of ints you want,
                but [int, str] can only accecpt a list who has exactly 2 elements.
                (if your data to serialize has more than 2 elements, the remaining elements may be
                lost)

    """
    from bigflow.core import entity

    if hasattr(rtype, 'serialize') and hasattr(rtype, 'deserialize'):
        return rtype

    if isinstance(rtype, Serde):
        return rtype

    if isinstance(rtype, entity.EntitiedBySelf):
        raise Exception("Not Support this serde :", rtype)

    if isinstance(rtype, type) and issubclass(rtype, message.Message):
        return proto_of(rtype)


    serde = {
        tuple: lambda: tuple_of(*rtype),
        list: lambda: list_of(*tuple(rtype)),
        set: lambda: set_of(list(rtype)[0]),
        dict: lambda: dict_of(rtype.keys()[0], rtype.values()[0])
    }

    if type(rtype) in serde:
        return serde[type(rtype)]()

"""
import sys
import struct
import marshal

from google.protobuf import message

from bigflow.core.serde import omnitypes_objector
from bigflow.core.serde import cloudpickle
from bigflow.core import entity
from bigflow import error

from bigflow_python.proto import types_pb2


class Serde(entity.EntitiedBySelf):
    """
    所有python实现的serde类要求继承于此类，用户可以通过继承Serde实现自定义的序列化/反序列化器

    >>> from bigflow import serde
    >>>
    >>> class CustomSerde(serde.Serde):
    ...     def serialize(self, obj):
    ...         assert(isinstance(obj, MyCostomObject))
    ...         return str(obj)
    ...     def deserialize(self, buf):
    ...         return MyCostomObject(buf)

    在大部分的变换中都可以传递一个特殊的叫serde的参数，
    设置该参数即可指定产出的PCollection的serde。

        p.map(lambda x: MyCostomObject(x), serde=CustomSerde())