pub fn diff(
    s: &Series,
    n: i64,
    null_behavior: NullBehavior
) -> Result<Series, PolarsError>Available on crate feature 
polars-ops only.pub fn diff(
    s: &Series,
    n: i64,
    null_behavior: NullBehavior
) -> Result<Series, PolarsError>polars-ops only.