[Python] Polars - Replace letter in string with uppercase letter

Is there any way in polars to replace character just after the _ with uppercase using regex replace? So far I have achieved it using polars.Expr.map_elements.

Is there any alternative using native expression API?

import re
import polars as pl

# Initialize
df = pl.DataFrame(
{
"id": [
"accessible_bidding_strategy.id",
"accessible_bidding_strategy.name",
"accessible_bidding_strategy.owner_customer_id",
]
}
)

# Transform
df = df.with_columns(
pl.col("id")
.map_elements(
lambda val: re.sub(r"_\w", lambda match: match.group(0)[1].upper(), val),
return_dtype=pl.String,
)
.alias("parsed_id")
)


print(df)

Output


shape: (3, 2)
┌───────────────────────────────────────────────┬───────────────────────────────────────────┐
│ id ┆ parsed_id │
│ --- ┆ --- │
│ str ┆ str │
╞═══════════════════════════════════════════════╪═══════════════════════════════════════════╡
│ accessible_bidding_strategy.id ┆ accessibleBiddingStrategy.id │
│ accessible_bidding_strategy.name ┆ accessibleBiddingStrategy.name │
│ accessible_bidding_strategy.owner_customer_id ┆ accessibleBiddingStrategy.ownerCustomerId │
└───────────────────────────────────────────────┴───────────────────────────────────────────┘

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