ability to cast python timedelta to `Duration`

[universalmind303]

Is your feature request related to a problem? Please describe.

I want to be able to cast a timedelta to a duration the same way we implicitly convert it if using from_pydict

import daft
import datetime

df = daft.from_pydict(
    {
        "time_delta": [datetime.timedelta(days=1), datetime.timedelta(days=2)],
    }
)
df.collect()

╭────────────────────────╮
│ time_delta             │
│ ---                    │
│ Duration[Microseconds] │
╞════════════════════════╡
│ 86400000000            │
├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
│ 172800000000           │
╰────────────────────────╯
(Showing first 2 of 2 rows)

Describe the solution you'd like

df.select(daft.lit(datetime.timedelta(days=1)).cast(daft.DataType.duration('us')))

Describe alternatives you've considered A clear and concise description of any alternative solutions or features you've considered.

Additional context Add any other context or screenshots about the feature request here.