https://paritytech.github.io/polkadot-sdk/master/sp_std/ops/struct.RangeFull.html
RangeFull in sp_std::ops - Rust
An unbounded range (`..`).
spstdopsrust
https://doc.rust-lang.org/beta/core/ops/struct.RangeFull.html
RangeFull in core::ops - Rust
An unbounded range (`..`).
coreopsrust