I see tons of examples of how to convert or operate on specific columns, where the column name is known and simple, like 'a' or 'b'.

I Have hundreds, maybe thousands of columns in thousands of dataframes and csv files. These Columns are annoyingly in PascalCase and very long, arbitrary words.

The rows in these columns are of Struct type. I want them in a different type. Any type, but help me start with either Float, Int, or String for now.

For argument's sake, please give me a second solution where only one, or two columns, are already in Str, but the rest are Struct and to be converted.

I've tried playing around with the following but keep failing:

df.with_columns()

pl.Series(df.rows(named=True)).to_list()

df.select(pl.col(pl.Utf8)).select(pl.all().n_unique())

df.select(pl.concat_list(pl.all.struct.field("*")).explode())