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having a weird issue that I haven’t seen anything similar to before: I’m trying to run a `BigQueryLoadGoogleCloudStorage` task (which I wrote but that isn’t really helping :grimacing:) and passing in `schema` as a list; by the time `schema` is used in `run`, somehow the order of the list is being altered, causing the columns to be mis-identified. any idea what might be messing with the `schema` input to my task? some kind of argument validation or copy maybe…?
context: <https://github.com/PrefectHQ/prefect/blob/master/src/prefect/tasks/google/bigquery.py#L346-L409>

Hey Brett — I think it might be the same issue as <https://prefect-community.slack.com/archives/CL09KU1K7/p1574761775447400?thread_ts=1574761775.447400>

Try wrapping the schema in a `Constant(schema)` to force the order to be preserved

We need to improve introspection of lists-of-constants I think

yep that fixed it! I can see now why it works the way it does but it can definitely be counterintuitive (and you might not notice right away)

I’ve attempted to improve the situation here <https://github.com/PrefectHQ/prefect/pull/1829>