Function bitrate_from_kbps 

const fn bitrate_from_kbps(kbps: u32) -> Result<Bitrate, DecodeError>

Maps a bitrate in kbps (u32) to the mp3lame_encoder::Bitrate enum.

Returns Err(DecodeError::UnsupportedBitrate) if the value doesn’t correspond to any LAME CBR bitrate.