temp.py

    @api.multi
    def send_document(self, attachments=None, tmpl=False):
        self.ensure_one()
        ctxt = dict(self._context)
        # clean context send email crash with context
        tmpl = self.env.ref("xmild_template_mail")
        tmpl.with_context(ctxt).send_mail(  # noqa
            self.id, email_values={"attachment_ids": attachments}
        )