Convert local date to midnight UTC timestamp

today_to_midnight_utc.py

import pytz
from datetime import date, datetime, time

def today_to_midnight_utc(local_tz='UTC'):
    """
    Returns today's date (local timezone) as a midnight UTC timestamp.
    e.g. If date is 04/20/18, and server timezone is America/Los_Angeles:
    
    today_to_midnight_utc(local_tz='America/Los_Angeles')
    >> 1524182400
    """
    tz = pytz.timezone(local_tz)
    local_date = datetime.now(tz).date()
    midnight_no_tz = datetime.combine(local_date, time())
    midnight_tz = tz.localize(midnight_no_tz)
    midnight_utc = midnight_tz.astimezone(pytz.utc)
    return int(midnight_utc.timestamp())