[Python] How to calculate horizontal median

How to calculate horizontal median for numerical columns?

df = pl.DataFrame({"ABC":["foo", "bar", "foo"], "A":[1,2,3], "B":[2,1,None], "C":[1,2,3]})
print(df)

shape: (3, 4)
┌─────┬─────┬──────┬─────┐
│ ABC ┆ A ┆ B ┆ C │
│ --- ┆ --- ┆ --- ┆ --- │
│ str ┆ i64 ┆ i64 ┆ i64 │
╞═════╪═════╪══════╪═════╡
│ foo ┆ 1 ┆ 2 ┆ 1 │
│ bar ┆ 2 ┆ 1 ┆ 2 │
│ foo ┆ 3 ┆ null ┆ 3 │
└─────┴─────┴──────┴─────┘


I want to achieve the same as with the below pl.mean_horizontal, but get median instead of the mean. I did not find existing expression for this.

print(df.with_columns(pl.mean_horizontal(pl.col(pl.Int64)).alias("Horizontal Mean")))

shape: (3, 5)
┌─────┬─────┬──────┬─────┬─────────────────┐
│ ABC ┆ A ┆ B ┆ C ┆ Horizontal Mean │
│ --- ┆ --- ┆ --- ┆ --- ┆ --- │
│ str ┆ i64 ┆ i64 ┆ i64 ┆ f64 │
╞═════╪═════╪══════╪═════╪═════════════════╡
│ foo ┆ 1 ┆ 2 ┆ 1 ┆ 1.333333 │
│ bar ┆ 2 ┆ 1 ┆ 2 ┆ 1.666667 │
│ foo ┆ 3 ┆ null ┆ 3 ┆ 3.0 │
└─────┴─────┴──────┴─────┴─────────────────┘

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