aenum includes a Python stdlib Enum-compatible data type, as well
as a metaclass-based NamedTuple implementation and a NamedConstant
class.

An Enum is a set of symbolic names (members) bound to unique,
constant values. Within an enumeration, the members can be compared
by identity, and the enumeration itself can be iterated over.
Support exists for unique values, multiple values, auto-numbering,
and suspension of aliasing (members with the same value are not
identical), plus the ability to have values automatically bound to
attributes.

A NamedTuple is a class-based, fixed-length tuple with a name for
each possible position accessible using attribute-access notation
as well as the standard index notation.

A NamedConstant is a class whose members cannot be rebound; it
lacks all other Enum capabilities, however.