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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 remove_key(request: web.Request) -> web.Response: """ Remove a key. ``` DELETE /wifi/keys/:id -> 200 OK {message: 'Removed key keyfile.pem'} ``` """

    keys_dir = CONFIG['wifi_keys_dir']
    available_keys = os.listdir(keys_dir)
    requested_hash = request.match_info['key_uuid']
    if requested_hash not in available_keys:
        return web.json_response(
            {'message': 'No such key file {}'
             .format(requested_hash)},
            status=404)
    key_path = os.path.join(keys_dir, requested_hash)
    name = os.listdir(key_path)[0]
    shutil.rmtree(key_path)
    return web.json_response(
        {'message': 'Key file {} deleted'.format(name)},
        status=200)