Send text messages using email servers and SMS gateways.

send_texts.py

import smtplib


def send(message: str, username: str, password: str, phone: str) -> None:
    """Sends messages to phone using Gmail servers."""
    # Some SMS gateways may be outdated or different, i.e. @txt.att.net was @sms.att.net
    carriers = {
        'att':    '@txt.att.net',
        'tmobile': '@tmomail.net',
        'verizon':  '@vtext.com',
        'sprint':   '@page.nextel.com'
    }
    # Replace the number with your own, or consider using an argument\dict for multiple people.
    to_number = '{}{}'.format(phone, carriers['att'])
    auth = (username, password)

    # Establish a secure session with gmail's outgoing SMTP server using your gmail account
    server = smtplib.SMTP("smtp.gmail.com", 587)
    server.starttls()
    server.login(auth[0], auth[1])

    # Send text message through SMS gateway of destination number
    server.sendmail(auth[0], to_number, message)