[Python] Cast pl.Date to Unix epoch

Trying to convert a pl.Date column to UNIX epoch as is, without any timezone offset:

import datetime
import polars as pl

df = pl.DataFrame(
{'Date': [datetime.datetime.now().date()]}
)


Correct time (00:00:00) when converted to Datetime:

df.with_columns(
pl.col("Date").cast(pl.Datetime)
)


┌─────────────────────┐
│ Date │
│ --- │
│ datetime[μs] │
╞═════════════════════╡
│ 2023-06-10 00:00:00 │
└─────────────────────┘


Incorrect time when casting to timestamp:

datetime.datetime.fromtimestamp(
df.with_columns(
pl.col("Date").cast(pl.Datetime).dt.timestamp("ms").truediv(1_000)
).item()
)


datetime.datetime(2023, 6, 10, 8, 0) # (08:00:00)


As suggested, without casting to Datetime also produces the incorrect time. (08:00:00)

pl.col("Date").dt.timestamp("ms").truediv(1_000)

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