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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 _sendtpl(self, sender, to, subject, cc=None, bcc=None, attach=None, replyto=None, **kwargs):
 """ Send a Letter from SENDER to TO, with the subject SUBJECT. Use the current template, with KWARGS as the context. Arguments: - `sender`: unicode - `to`: unicode - `subject`: unicode - `cc`: str or [str] - `bcc`: str or [str] - `replyto`: str - `**kwargs`: objects Return: None Exceptions: None """

        plain, html = self.body(**kwargs)
        self.mailer.send(sender, to, subject, plain=plain, html=html, cc=cc, bcc=bcc,
                         replyto=replyto, attach=attach)
        return