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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 classic_email_send(self, subject, from_address, to, consent_to_track, client_id=None, cc=None, bcc=None, html=None, text=None, attachments=None, track_opens=True, track_clicks=True, inline_css=True, group=None, add_recipients_to_list=None):
 """Sends a classic email."""

        validate_consent_to_track(consent_to_track)
        body = {
            "Subject": subject,
            "From": from_address,
            "To": to,
            "CC": cc,
            "BCC": bcc,
            "HTML": html,
            "Text": text,
            "Attachments": attachments,
            "TrackOpens": track_opens,
            "TrackClicks": track_clicks,
            "InlineCSS": inline_css,
            "Group": group,
            "AddRecipientsToList": add_recipients_to_list,
            "ConsentToTrack": consent_to_track,
        }
        if client_id is None:
            response = self._post(
                "/transactional/classicEmail/send", json.dumps(body))
        else:
            response = self._post(
                "/transactional/classicEmail/send?clientID=%s" % client_id, json.dumps(body))
        return json_to_py(response)