How to use the marshmallow.post_load function in marshmallow

    @post_load
    def to_tuple(self, params, **kwargs):
        return params["lower_bound"], params["upper_bound"]

    @post_load
    def make_pagination(self, data):
        return Pagination(**data)

    @post_load
    def make_request(self, data):
        """Parse the outgoing schema"""
        callname = self.context.get("callname")
        try:
            payload = REQUEST_MAP[callname].dump(data)  # type: ignore
        except AttributeError:
            payload = None

        request = {
            "callname": callname,
            "payload": payload
        }
        return Request(**request)

    @marshmallow.post_load
    def post_load(self, data, **kwargs):
        del data["action"]
        return types.StagedOrderSetDeliveryItemsAction(**data)

    @post_load
    def remove_envelope(self, data):
        """Post process data."""
        # Remove envelope
        if 'metadata' in data:
            data = data['metadata']

        # Artificially insert our schema because invenio-deposit wants it.
        # TODO: Replace cd2hrepo... by configuration variable
        data['$schema'] = (
            'https://cd2hrepo.galter.northwestern.edu/'
            'schemas/records/record-v0.1.0.json'
        )

        return data

    @post_load
    def make_user(self, data):
        return User(**data)

    @post_load
    def make_experiment_run(self, data):
        return ExperimentRun(**data)

    @post_load
    def add_tenant_info(self, data):
        return data

    @post_load
    def make_credentials(self, data):
        return Credentials(**data)

    @post_load
    def make_resource(self, data):
        return Resource(**data)