@type t() :: %{required(integer()) => integer()}

A cose key

example

Example:

%{
  -3 => <<182, 81, 183, 218, 92, 107, 106, 120, 60, 51, 75, 104, 141, 130,
    119, 232, 34, 245, 84, 203, 246, 165, 148, 179, 169, 31, 205, 126, 241,
    188, 241, 176>>,
  -2 => <<89, 29, 193, 225, 4, 234, 101, 162, 32, 6, 15, 14, 130, 179, 223,
    207, 53, 2, 134, 184, 178, 127, 51, 145, 57, 180, 104, 242, 138, 96, 27,
    221>>,
  -1 => 1,
  1 => 2,
  3 => -7
}