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Hi! Having a look to the doc of the transforms for dataset ownership, it mentions:
&gt; If you’d like to add more complex logic for assigning ownership, you can use the more generic `add_dataset_ownership`<https://github.com/linkedin/datahub/blob/master/metadata-ingestion/src/datahub/ingestion/transformer/add_dataset_ownership.py| transformer>, which calls a user-provided function to determine the ownership of each dataset.
Is there any example of this? I’m not sure how to set such a function in the yaml. Also, does the function need to be registered somewhere? Thanks!

just taking a crack at it since im looking at adapting transformers now as well for browsepaths..
```source:
  type: mssql
  config:
    username: sa
    password: ${MSSQL_PASSWORD}
    database: DemoData
transformers:
  - type: "simple_add_dataset_ownership"
    config:
      owner_urns:
        - "urn:li:corpuser:username1"
        - "urn:li:corpuser:username2"
        - "urn:li:corpGroup:groupname"
sink:
  type: "datahub-rest"
  config:
    server: "<http://localhost:8080>"```
source: <https://github.com/linkedin/datahub/tree/master/metadata-ingestion>

This :point_up: is the example for the `simple_add_dataset_ownership`. However I’m looking for an example for the `add_dataset_ownership` transform. The particularity of this transform if that the config is a callback function. So I want to understand _eg_ whether it requires some registration.

I would also be interested in having an example of how to add a custom transformer.  I guess this <https://github.com/linkedin/datahub/pull/2580/files> can serve as an example
Without having to open a PR to the main repository would be a plus (in case the transformer is business specific) or we want a feature which might take the team some time to implement due to other priorities.

<@U01GZEETMEZ> ^ can you please point to an example? also, you don't need to contribute back the custom transformer to OSS

<@U027ZS25RFS> <@U01TCN40JKV> <@U027B7R23J4> Here’s how you can use a full custom transformer:
```transformers:
  # Assuming `from <http://import.path.to|import.path.to> import MyTransformer` works and is derived from the Transformer base class:
  - type: "import.path.to.MyTransfomer"
    config:
      some_property: "some.value"```
To define the function of the add_dataset_owners or add_dataset_tags, once this PR is merged <https://github.com/linkedin/datahub/pull/2858>, you can do something along these lines:
```transformers:
  - type: "add_dataset_tags"
    config:
      get_tags_to_add: "import.path.to.myfunction" # assuming `from <http://import.path.to|import.path.to> import myfunction` works```

Nice! That’s exactly what I was looking for :ok_hand:, thanks!