/clients endpoint not working

[slinlee]

internal server error

ERROR:    Exception in ASGI application
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/uvicorn/protocols/http/httptools_impl.py", line 371, in run_asgi
    result = await app(self.scope, self.receive, self.send)
  File "/usr/local/lib/python3.7/site-packages/uvicorn/middleware/proxy_headers.py", line 59, in __call__
    return await self.app(scope, receive, send)
  File "/usr/local/lib/python3.7/site-packages/fastapi/applications.py", line 199, in __call__
    await super().__call__(scope, receive, send)
  File "/usr/local/lib/python3.7/site-packages/starlette/applications.py", line 112, in __call__
    await self.middleware_stack(scope, receive, send)
  File "/usr/local/lib/python3.7/site-packages/starlette/middleware/errors.py", line 181, in __call__
    raise exc from None
  File "/usr/local/lib/python3.7/site-packages/starlette/middleware/errors.py", line 159, in __call__
    await self.app(scope, receive, _send)
  File "/usr/local/lib/python3.7/site-packages/starlette/exceptions.py", line 82, in __call__
    raise exc from None
  File "/usr/local/lib/python3.7/site-packages/starlette/exceptions.py", line 71, in __call__
    await self.app(scope, receive, sender)
  File "/usr/local/lib/python3.7/site-packages/starlette/routing.py", line 580, in __call__
    await route.handle(scope, receive, send)
  File "/usr/local/lib/python3.7/site-packages/starlette/routing.py", line 241, in handle
    await self.app(scope, receive, send)
  File "/usr/local/lib/python3.7/site-packages/starlette/routing.py", line 52, in app
    response = await func(request)
  File "/usr/local/lib/python3.7/site-packages/fastapi/routing.py", line 215, in app
    dependant=dependant, values=values, is_coroutine=is_coroutine
  File "/usr/local/lib/python3.7/site-packages/fastapi/routing.py", line 149, in run_endpoint_function
    return await dependant.call(**values)
  File "./app.py", line 109, in clients
    return FileResponse(path="clients.zip", filename="clients.zip")
  File "/usr/local/lib/python3.7/site-packages/starlette/responses.py", line 247, in __init__
    assert aiofiles is not None, "'aiofiles' must be installed to use FileResponse"
AssertionError: 'aiofiles' must be installed to use FileResponse
INFO:     10.20.12.253:56266 - "GET /policy/id4350/ HTTP/1.1" 200 OK
INFO:     10.20.12.253:56278 - "GET /policy/id4350/ HTTP/1.1" 200 OK
INFO:     10.20.12.253:56452 - "GET /policy/id4350/ HTTP/1.1" 200 OK
INFO:     10.20.12.253:56460 - "GET /policy/id4350/ HTTP/1.1" 200 OK
INFO:     10.20.12.253:56614 - "GET /policy/id4350/ HTTP/1.1" 200 OK
INFO:     10.20.12.253:56624 - "GET /policy/id4350/ HTTP/1.1" 200 OK
INFO:     10.20.12.253:56756 - "GET /policy/id4350/ HTTP/1.1" 200 OK
INFO:     10.20.12.253:56766 - "GET /policy/id4350/ HTTP/1.1" 200 OK```