There was a ticket open for this back in March (#30169), it was closed out due to inactivity and there was a comment that it was related to an upstream issue in looker_sdk. I took a look at the issue in looker_sdk and it didn't quite seem like the same thing.

After digging in, I believe this is simply a typo in the hook's get_looker_sdk() method and the 40 was left off by mistake. Adding the 40 back on here fixes the issues in my local environment. I can't seem to find any reason it would be desirable to use serialize.serialize there, and in fact looker_sdk uses serialize40 here.

You can see here in the looker_sdk repo that during init we use serialize.serialize40, whereas in LookerHook we use serialize.serialize.

serialize.serialize points here, where it expects a converter to be passed in.

serialize.serialize40 points here, where there is a default converter set.

This becomes problematic when you want to do something with the sdk from LookerHook when calling a method using post, like create_query.

An example - when we try to do something like this, we get an error due to the missing converter:

def example():
  sdk = LookerHook("looker_conn").get_looker_sdk()

  query = sdk.create_query(
    body=models.WriteQuery(
      model="my_model",
      view="my_explore",
      fields=["field1"],
    )
  )

with DAG(...) as dag:
  PythonOperator(task_id="example", python_callable=example)

This generates the error: TypeError: serialize() missing 1 required keyword-only argument: 'converter'

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