How to create a Python decorator that can wrap either coroutine or function?

May be you can find better way to do it, but, for example, you can just move your wrapping logic to some context manager to prevent code duplication:

import asyncio
import functools
import time
from contextlib import contextmanager


def duration(func):
    @contextmanager
    def wrapping_logic():
        start_ts = time.time()
        yield
        dur = time.time() - start_ts
        print('{} took {:.2} seconds'.format(func.__name__, dur))

    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        if not asyncio.iscoroutinefunction(func):
            with wrapping_logic():
                return func(*args, **kwargs)
        else:
            async def tmp():
                with wrapping_logic():
                    return (await func(*args, **kwargs))
            return tmp()
    return wrapper