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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 increment_download_count(self, id, attachmentID, doc_type='book'):
        '''
        Increment the download counter of a specific file
        '''
        body = self.es.get(index=self.index_name, id=id, doc_type='book', _source_include='_attachments')['_source']

        for attachment in body['_attachments']:
            if attachment['id'] == attachmentID:
                attachment['download_count'] += 1
                self.es.update(index=self.index_name,
                               id=id,
                               doc_type=doc_type,
                               body={"doc": {'_attachments': body['_attachments']}})
                return
        raise NotFoundError("No attachment could be found with id: {}".format(attachmentID))