This is a simple python file for the demo "gWall: gWall: LCD+RasPi+Google Assistant" (https://www.youtube.com/watch?v=Y-H_3o7vKcc)

gwall.py

#!/usr/bin/env python

# Copyright (C) 2017 Google Inc.
# Copyright (C) 2017 Ryosuke Tajima
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


from __future__ import print_function

import argparse
import os.path
import json
import uinput

import google.oauth2.credentials

from google.assistant.library import Assistant
from google.assistant.library.event import EventType
from google.assistant.library.file_helpers import existing_file

device = uinput.Device(
    [uinput.KEY_ENTER, uinput.KEY_M, uinput.KEY_W, uinput.KEY_D, uinput.KEY_X])

def process_event(assistant, event):
    """Pretty prints events.

    Prints all events that occur with two spaces between each new
    conversation and a single space between turns of a conversation.

    Args:
        event(event.Event): The current event to process.
    """
    if event.type == EventType.ON_CONVERSATION_TURN_STARTED:
        device.emit_click(uinput.KEY_ENTER)
        print()

    print(event)
    
    # Process for google calendar in Chrome
    if event.type == EventType.ON_RECOGNIZING_SPEECH_FINISHED:
        print(event.args['text'])
        if 'calendar' in event.args['text']:
            assistant.stop_conversation()
            if 'day' in event.args['text']:
                device.emit_click(uinput.KEY_D)
            elif 'week' in event.args['text']:
                device.emit_click(uinput.KEY_W)
            elif 'month' in event.args['text']:
                device.emit_click(uinput.KEY_M)
            elif 'custom' in event.args['text']:
                device.emit_click(uinput.KEY_X)

def main():
    parser = argparse.ArgumentParser(
        formatter_class=argparse.RawTextHelpFormatter)
    parser.add_argument('--credentials', type=existing_file,
                        metavar='OAUTH2_CREDENTIALS_FILE',
                        default=os.path.join(
                            os.path.expanduser('~/.config'),
                            'google-oauthlib-tool',
                            'credentials.json'
                        ),
                        help='Path to store and read OAuth2 credentials')
    args = parser.parse_args()
    with open(args.credentials, 'r') as f:
        credentials = google.oauth2.credentials.Credentials(token=None,
                                                            **json.load(f))

    with Assistant(credentials) as assistant:
        for event in assistant.start():
            process_event(assistant, event)


if __name__ == '__main__':
    main()