[Python] How can I filter a list within a Polars column?

Say for example I have data like this:

import polars as pl

df = pl.DataFrame(
{
"subject": ["subject1", "subject2"],
"emails": [
["samATxyz.com", "janeATxyz.com", "jimATcustomer.org"],
["samATxyz.com", "zaneATxyz.com", "basATcustomer.org", "jimATcustomer.org"],
],
}
)

df


shape: (2, 2)
┌──────────┬─────────────────────────────────────────────────────────────────────────────┐
│ subject ┆ emails │
│ --- ┆ --- │
│ str ┆ list[str] │
╞══════════╪═════════════════════════════════════════════════════════════════════════════╡
│ subject1 ┆ ["samATxyz.com", "janeATxyz.com", "jimATcustomer.org"] │
│ subject2 ┆ ["samATxyz.com", "zaneATxyz.com", "basATcustomer.org", "jimATcustomer.org"] │
└──────────┴─────────────────────────────────────────────────────────────────────────────┘


I want to filter the data so that the emails column only contain emails that end in "ATxyz.com".

shape: (2, 2)
┌──────────┬───────────────────────────────────┐
│ subject ┆ emails │
│ --- ┆ --- │
│ str ┆ list[str] │
╞══════════╪═══════════════════════════════════╡
│ subject1 ┆ ["samATxyz.com", "janeATxyz.com"] │
│ subject2 ┆ ["samATxyz.com", "zaneATxyz.com"] │
└──────────┴───────────────────────────────────┘


How can I do this using polars?

I had a few ideas, but I cannot figure out the right syntax, or it seems more complex/verbose than I would expect:

• Maybe I could somehow filter the data using .list.eval(pl.element() ..., but I cannot figure out how to filter items in the list with this syntax.
• I could reshape the data using .explode, but this seems verbose and more complex than needed.

This is as close as I have got

import polars as pl

df = pl.DataFrame(
{
"subject": ["subject1", "subject2"],
"emails": [
["samATxyz.com", "janeATxyz.com", "jimATcustomer.org"],
["samATxyz.com", "zaneATxyz.com", "basATcustomer.org", "jimATcustomer.org"],
],
}
)

df.with_columns(
pl.col("emails").list.eval(pl.element().str.contains("ATxyz")),
)


shape: (2, 2)
┌──────────┬────────────────────────────┐
│ subject ┆ emails │
│ --- ┆ --- │
│ str ┆ list[bool] │
╞══════════╪════════════════════════════╡
│ subject1 ┆ [true, true, false] │
│ subject2 ┆ [true, true, false, false] │
└──────────┴────────────────────────────┘

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