Hey all 🙂 We got the following error when trying to map over a list of dictionaries. First just to clarify: mapping over a list of dictionaries should be fine, right? Second, what could be the reason for the message?

Hi Robin, mapping over a list of dictionaries should be fine. The error you're getting here is happening in your task here (the actual mapping appears to be working correctly) - looks like you're getting a list where you expected a dict - perhaps you're passing in a list of lists instead?

Good point! Thanks for the quick feedback 🙂

That'd work, you could also make use of the new(ish)

prefect.flatten

, which will do that for you (but potentially in a more efficient way).

your_task.map(flatten(list_of_lists))

See https://docs.prefect.io/core/concepts/mapping.html#flat-mapping for more info.

Thanks for the tip! that looks neat 🙂