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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 pids2ore(in_stream, fmt='xml', base_url='https://cn.dataone.org/cn'):
 """read pids from in_stream and generate a resource map. first pid is the ore_pid second is the sci meta pid remainder are data pids """

    pids = []
    for line in in_stream:
        pid = line.strip()
        if len(pid) > 0:
            if not pid.startswith("# "):
                pids.append(pid)
    if (len(pids)) < 2:
        raise ValueError("Insufficient identifiers provided.")

    logging.info("Read %d identifiers", len(pids))

    ore = ResourceMap(base_url=base_url)

    logging.info("ORE PID = %s", pids[0])
    ore.initialize(pids[0])

    logging.info("Metadata PID = %s", pids[1])
    ore.addMetadataDocument(pids[1])

    ore.addDataDocuments(pids[2:], pids[1])
    return ore.serialize_to_display(doc_format=fmt)