ValueError: Expected iterable of tuples of (name, dtype), got ['archived', 'author',....]

I am trying to replicate the example of this page: http://blaze.pydata.org/blog/2015/09/08/reddit-comments/ about castra, dask and reddit comments, and I get this error when I run the dd.from_castra(data,columns). My castra file took some hours to be created but it is clean and exactly as the tutorial mentions.

Can you please check?

Start by reproducing the error from the Reddit comments tutorial at the linked blog page, using the dd.from_castra(data, columns) entry point mentioned in the report. Compare the tutorial's castra and dask usage with the reported ValueError; done means the example works or the incompatibility and required correction are documented.

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