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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def list_keys(request: web.Request) -> web.Response: """ List keys in the authorized_keys file. GET /server/ssh_keys -> 200 OK {"public_keys": [{"key_md5": md5 hex digest, "key": key string}]} (or 403 if not from the link-local connection) """

    return web.json_response(
        {'public_keys': [{'key_md5': details[0], 'key': details[1]}
                         for details in get_keys()]},
        status=200)