Enum Module: Create Robust Enumerations for Cleaner Code

from enum import Enum

class Color(Enum):
    RED = 1
    GREEN = 2
    BLUE = 3

# Usage
print(Color.RED)        # Color.RED
print(Color.RED.name)   # RED
print(Color.RED.value)  # 1

# Comparison works
favorite = Color.BLUE
if favorite == Color.BLUE:
    print("Blue is beautiful!")

# Iteration
for color in Color:
    print(f"{color.name}: {color.value}")

from enum import Enum, auto

class Status(Enum):
    PENDING = auto()
    APPROVED = auto()
    REJECTED = auto()
    CANCELLED = auto()

print(Status.PENDING.value)   # 1
print(Status.APPROVED.value)  # 2

# String values with auto
class Direction(Enum):
    def _generate_next_value_(name, start, count, last_values):
        return name.lower()
    
    NORTH = auto()  # 'north'
    SOUTH = auto()  # 'south'
    EAST = auto()   # 'east'
    WEST = auto()   # 'west'

from enum import Enum

# Create enum using functional API
HttpStatus = Enum('HttpStatus', 'OK NOT_FOUND SERVER_ERROR')
print(HttpStatus.OK)        # HttpStatus.OK
print(HttpStatus.OK.value)  # 1

# With custom values
HttpStatus = Enum('HttpStatus', {
    'OK': 200,
    'NOT_FOUND': 404,
    'SERVER_ERROR': 500
})
print(HttpStatus.NOT_FOUND.value)  # 404

from enum import IntEnum

class Priority(IntEnum):
    LOW = 1
    MEDIUM = 2
    HIGH = 3
    CRITICAL = 4

# Can be used in numeric operations
task_priority = Priority.HIGH
if task_priority > Priority.MEDIUM:
    print("High priority task!")

# Works with comparison to regular integers
if task_priority >= 3:
    print("Priority level 3 or higher")

# Sorting works naturally
priorities = [Priority.LOW, Priority.CRITICAL, Priority.MEDIUM]
sorted_priorities = sorted(priorities)
print(sorted_priorities)  # [Priority.LOW, Priority.MEDIUM, Priority.CRITICAL]

from enum import Flag, auto

class Permission(Flag):
    READ = auto()
    WRITE = auto()
    EXECUTE = auto()

# Combine permissions
user_perms = Permission.READ | Permission.WRITE
print(user_perms)  # Permission.WRITE|READ

# Check permissions
if Permission.READ in user_perms:
    print("User can read")

if user_perms & Permission.WRITE:
    print("User can write")

# All permissions
admin_perms = Permission.READ | Permission.WRITE | Permission.EXECUTE
print(admin_perms)  # Permission.EXECUTE|WRITE|READ

from enum import Enum

class HTTPStatus(Enum):
    OK = 200
    CREATED = 201
    BAD_REQUEST = 400
    UNAUTHORIZED = 401
    NOT_FOUND = 404
    SERVER_ERROR = 500
    
    def __str__(self):
        return f"{self.value} {self.name.replace('_', ' ').title()}"
    
    @property
    def is_success(self):
        return 200 <= self.value < 300
    
    @property
    def is_client_error(self):
        return 400 <= self.value < 500

# Usage
status = HTTPStatus.NOT_FOUND
print(status)              # 404 Not Found
print(status.is_success)   # False
print(status.is_client_error)  # True

from enum import Enum, auto

class GameState(Enum):
    MENU = auto()
    PLAYING = auto()
    PAUSED = auto()
    GAME_OVER = auto()
    
    def can_transition_to(self, new_state):
        transitions = {
            GameState.MENU: [GameState.PLAYING],
            GameState.PLAYING: [GameState.PAUSED, GameState.GAME_OVER],
            GameState.PAUSED: [GameState.PLAYING, GameState.MENU],
            GameState.GAME_OVER: [GameState.MENU, GameState.PLAYING]
        }
        return new_state in transitions.get(self, [])

# Usage
current_state = GameState.MENU
if current_state.can_transition_to(GameState.PLAYING):
    print("Starting game!")

from enum import Enum

class LogLevel(Enum):
    DEBUG = 10
    INFO = 20
    WARNING = 30
    ERROR = 40
    CRITICAL = 50
    
    def __ge__(self, other):
        if self.__class__ is other.__class__:
            return self.value >= other.value
        return NotImplemented
    
    def __gt__(self, other):
        if self.__class__ is other.__class__:
            return self.value > other.value
        return NotImplemented

class Config(Enum):
    LOG_LEVEL = LogLevel.INFO
    MAX_RETRIES = 3
    TIMEOUT = 30
    
    @classmethod
    def get(cls, key, default=None):
        try:
            return cls[key].value
        except KeyError:
            return default

# Usage
if LogLevel.DEBUG >= Config.LOG_LEVEL.value:
    print("Debug logging enabled")

from enum import Enum, unique

@unique
class Color(Enum):
    RED = 1
    GREEN = 2
    BLUE = 3
    # CRIMSON = 1  # This would raise ValueError due to @unique

# Aliases (when you want them)
class Color(Enum):
    RED = 1
    GREEN = 2
    BLUE = 3
    CRIMSON = 1  # Alias for RED

print(Color.RED is Color.CRIMSON)  # True

from enum import Enum

class Planet(Enum):
    MERCURY = (3.303e+23, 2.4397e6)
    VENUS   = (4.869e+24, 6.0518e6)
    EARTH   = (5.976e+24, 6.37814e6)
    MARS    = (6.421e+23, 3.3972e6)
    
    def __init__(self, mass, radius):
        self.mass = mass       # in kilograms
        self.radius = radius   # in meters
    
    @property
    def surface_gravity(self):
        # universal gravitational constant
        G = 6.67300E-11
        return G * self.mass / (self.radius * self.radius)

print(Planet.EARTH.surface_gravity)  # 9.802652743337129

# Use enums instead of constants
# Bad
STATUS_PENDING = 1
STATUS_APPROVED = 2
STATUS_REJECTED = 3

# Good
class Status(Enum):
    PENDING = 1
    APPROVED = 2
    REJECTED = 3

# Use meaningful names and values
class ResponseFormat(Enum):
    JSON = "application/json"
    XML = "application/xml"
    HTML = "text/html"

# Group related constants
class DatabaseSettings(Enum):
    HOST = "localhost"
    PORT = 5432
    DATABASE = "myapp"
    TIMEOUT = 30