mailgun.py

    def _send(self, email_message):
        from_email = sanitize_address(email_message.from_email, email_message.encoding)
        recipients = [sanitize_address(addr, email_message.encoding)
                      for addr in email_message.recipients()]

        try:
            post_data = []
            post_data.append(('to', (",".join(recipients)),))
            post_data.append(('text', email_message.body,))
            post_data.append(('subject', email_message.subject,))
            post_data.append(('from', from_email,))

            if email_message.alternatives:
                for alt in email_message.alternatives:
                    if alt[1] == 'text/html':
                        post_data.append(('html', alt[0],))
                        break

            if email_message.attachments:
                for attachment in email_message.attachments:
                    post_data.append(('attachment', attachment[1],))

                response = requests.post(self._api_url + "messages",
                                         auth=("api", self._access_key),
                                         files=post_data)
            else:

                response = requests.post(self._api_url + "messages",
                                         auth=("api", self._access_key),
                                         data=post_data)