https://doc.rust-lang.org/beta/core/fmt/struct.DebugSet.html
DebugSet in core::fmt - Rust
A struct to help with `fmt::Debug` implementations.
corefmtrust
https://dev-doc.rust-lang.org/stable/std/fmt/struct.DebugSet.html
DebugSet in std::fmt - Rust
A struct to help with `fmt::Debug` implementations.
stdfmtrust