pub trait PolarsMonthStart {
// Required method
fn month_start(&self, time_zone: Option<&Tz>) -> Result<Self, PolarsError>
where Self: Sized;
}
pub trait PolarsMonthStart {
// Required method
fn month_start(&self, time_zone: Option<&Tz>) -> Result<Self, PolarsError>
where Self: Sized;
}