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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 _parse_outgoing_mail(sender, to, msgstring):
 """ Parse an outgoing mail and put it into the OUTBOX. Arguments: - `sender`: str - `to`: str - `msgstring`: str Return: None Exceptions: None """

    global OUTBOX
    OUTBOX.append(email.message_from_string(msgstring))
    return