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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 onion_study(in_conn, out_conn, data_source):
 """Build and index for onion from a given Git index. :param in_conn: ESPandasConnector to read from. :param out_conn: ESPandasConnector to write to. :param data_source: name of the date source to generate onion from. :return: number of documents written in ElasticSearch enriched index. """

    onion = OnionStudy(in_connector=in_conn, out_connector=out_conn, data_source=data_source)
    ndocs = onion.analyze()
    return ndocs