list.to_struct().struct.unnest() fails

[mcrumiller]

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• I have confirmed this bug exists on the latest version of Polars.

Issue description

When a list is converted to a struct, unnest() cannot be called immediately afterwards.

import polars as pl

df = pl.DataFrame({"a": [[1, 2, 3]]})
df.select(pl.col("a").list.to_struct().struct.unnest())
# polars.exceptions.InvalidOperationError: expected 'struct'

Installed versions

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