[Python] Python - object MagicMock can't be used in 'await' expression

When I was trying to mock an async function in unittest with MagicMock, I got this exception:

TypeError: object MagicMock can't be used in 'await' expression
​

With sample code like:

# source code
class Service:
async def compute(self, x):
return x

class App:
def __init__(self):
self.service = Service()

async def handle(self, x):
return await self.service.compute(x)

# test code
import asyncio
import unittest
from unittest.mock import patch


class TestApp(unittest.TestCase):
@patch('__main__.Service')
def test_handle(self, mock):
loop = asyncio.get_event_loop()
app = App()
res = loop.run_until_complete(app.handle('foo'))
app.service.compute.assert_called_with("foo")

if __name__ == '__main__':
unittest.main()


How should I fix it with built-in python3 libraries?

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