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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:
 def main():
 """ Do the things! Return: 0 Exceptions: """

    description = 'Letter - a commandline interface'
    parser = argparse.ArgumentParser(description=description)
    parser.add_argument('--gmail', action='store_true', help='Send via Gmail', )
    args = parser.parse_args()

    to       = raw_input('To address > ')
    subject  = raw_input('Subject > ')
    body     = raw_input('Your Message > ')


    if args.gmail:
        user = fromaddr = raw_input('Gmail Address > ')
        pw   = getpass.getpass()
        postie = letter.GmailPostman(user=user, pw=pw)
    else:
        postie = letter.Postman() # Unauthorized SMTP, localhost:25
        fromaddr = raw_input('From address > ')

    class Message(letter.Letter):
        Postie     = postie

        From       = fromaddr
        To         = to
        Subject    = subject
        Body       = body

    return 0