Python sync-async decorator factory

sync_async_deco.py

class SyncAsyncDecoratorFactory:
    """
    Factory creates decorator which can wrap either a coroutine or function.
    To return something from wrapper use self._return
    If you need to modify args or kwargs, you can yield them from wrapper
    """
    def __new__(cls, *args, **kwargs):
        instance = super().__new__(cls)
        # This is for using decorator without parameters
        if len(args) == 1 and not kwargs and (inspect.iscoroutinefunction(args[0]) or inspect.isfunction(args[0])):
            instance.__init__()
            return instance(args[0])
        return instance

    class ReturnValue(Exception):
        def __init__(self, return_value):
            self.return_value = return_value

    @contextmanager
    def wrapper(self, *args, **kwargs):
        raise NotImplementedError

    @classmethod
    def _return(cls, value):
        raise cls.ReturnValue(value)

    def __call__(self, func):
        @wraps(func)
        def call_sync(*args, **kwargs):
            try:
                with self.wrapper(*args, **kwargs) as new_args:
                    if new_args:
                        args, kwargs = new_args
                    return self.func(*args, **kwargs)
            except self.ReturnValue as r:
                return r.return_value

        @wraps(func)
        async def call_async(*args, **kwargs):
            try:
                with self.wrapper(*args, **kwargs) as new_args:
                    if new_args:
                        args, kwargs = new_args
                    return await self.func(*args, **kwargs)
            except self.ReturnValue as r:
                return r.return_value

        self.func = func
        return call_async if inspect.iscoroutinefunction(func) else call_sync

This class is cool! Thanks!