A script that watches prime now for stock, sending a webhook to Zapier which you can configure to send you an SMS, Slack, whatever...

nintendo-switch-getter.py

import time
import bs4
import requests
import logging
import sys

logger = logging.getLogger('switchlogger')
logger.setLevel(logging.DEBUG)

ch = logging.StreamHandler(sys.stdout)
ch.setLevel(logging.DEBUG)
formatter = logging.Formatter('%(asctime)s - %(message)s')
ch.setFormatter(formatter)
logger.addHandler(ch)

ZIP_CODE = 12345  # get you a zip code
ZAPIER_WEBHOOK_URL = 'https://hooks.zapier.com/hooks/catch/N/ABCDEFG/'  # get you a webhook -> sms zapier.com

SEARCH_STRING = 'Nintendo Switch'
PRODUCT_IDS = {'B01MUAGZ49', 'B01LTHP2ZK'}

POLL_INTERVAL = 5
ALERT_EVERY_SECONDS = 60
LAST_ALERT_UNIX = time.time() - ALERT_EVERY_SECONDS

USER_AGENT = 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36'

MAIN_URL = 'https://primenow.amazon.com'
SEARCH_URL = '{}/search'.format(MAIN_URL)

if __name__ == '__main__':
    session = requests.Session()
    session.headers['User-Agent'] = USER_AGENT
    session.post(MAIN_URL, data={'newPostalCode': ZIP_CODE})  # login
    logger.debug('logging in for {}'.format(ZIP_CODE))

    while True:
        response = session.get(SEARCH_URL, params={'k': SEARCH_STRING})
        soup = bs4.BeautifulSoup(response.text, 'html.parser')
        logger.debug('searching for {}'.format(SEARCH_STRING))

        for product_id in PRODUCT_IDS:
            filtered = soup.select('div#house-search-result div#asin-card-{}'.format(product_id))
            if filtered:
                if LAST_ALERT_UNIX < time.time():
                    logger.debug('!!! found for {} !!!'.format(product_id))
                    LAST_ALERT_UNIX = time.time() + ALERT_EVERY_SECONDS
                    requests.post(ZAPIER_WEBHOOK_URL, json={
                        'product_id': product_id,
                        'zip_code': ZIP_CODE
                    })
                else:
                    logger.debug('found but silent for last alert'.format(product_id))

        time.sleep(POLL_INTERVAL)