Template for Python decorator function and class

decorator.py

import functools


def decorator(function):
    """A general decorator function"""

    @functools.wraps(function)
    def wrapper(*args, **kwargs):
        # Write decorator function logic here
        # Before function call
        # ...
        result = function(*args, **kwargs)
        # After function call
        # ...
        return result
    return wrapper


def decorator_with_args(func=None, *, arg=None):
    """Decorator function with arguments

    Decorator can be used with or without arguments

    Examples:
        >>>
        >>> @decorator_with_args
        >>> def func():
        >>>     pass
        >>>
        >>> @decorator_with_args(arg='foo')
        >>> def func():
        >>>     pass
        >>>
    """

    # 1. Decorator arguments are applied to itself as partial arguments
    if func is None:
        return functools.partial(decorator_with_args, arg=arg)

    # 2. logic with the arguments
    ...

    # 3. Handles the actual decorating
    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        # Write decorator function logic here
        # Before function call
        # ...
        result = func(*args, **kwargs)
        # After function call
        # ...
        return result
    return wrapper


class decorator_class(object):
    """General decorator class"""

    def __init__(self, *args, **kwargs):
        """Decorator arguments"""
        pass

    def __call__(self, function):
        @functools.wraps(function)
        def wrapper(*args, **kwargs):
            # Write decorator function logic here
            # Before function call
            # ...
            result = function(*args, **kwargs)
            # After function call
            # ...
            return result
        return wrapper