Advanced Enumerations (compatible with Python's stdlib Enum), NamedTuples, and NamedConstants

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.

Enum classes:

Enum: Base class for creating enumerated constants.
IntEnum: Base class for creating enumerated constants that are also subclasses of int.
Flag: Base class for creating enumerated constants that can be combined using the bitwise operations without losing their Flag membership.
IntFlag: Base class for creating enumerated constants that can be combined using the bitwise operators without losing their IntFlag membership. IntFlag members are also subclasses of int.
AutoNumberEnum: Derived class that automatically assigns an int value to each member.
OrderedEnum: Derived class that adds <, <=, >=, and > methods to an Enum.
UniqueEnum: Derived class that ensures only one name is bound to any one value.

Utility functions include:

convert: helper to convert target global variables into an Enum
constant: helper class for creating constant members
enum: helper class for creating members with keywords
enum_property: property to enable enum members to have same named attributes (e.g. name and value)
export: helper to insert Enum members into a namespace (usually globals())
extend_enum: add new members to enumerations after creation
module: inserts NamedConstant and Enum classes into sys.modules where it will appear to be a module whose top-level names cannot be rebound
skip: class that prevents attributes from being converted to a constant or enum member
unique: decorator that ensures no duplicate members