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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 extract(d, whichtables, mode, time):
 """ LiPD Version 1.3 Main function to initiate LiPD to TSOs conversion. Each object has a "paleoNumber" or "chronNumber" "tableNumber" "modelNumber" "time_id" "mode" - chronData or paleoData "tableType" - "meas" "ens" "summ" :param dict d: Metadata for one LiPD file :param str whichtables: all, meas, summ, or ens :param str mode: paleo or chron mode :return list _ts: Time series """

    logger_ts.info("enter extract_main")
    _root = {}
    _ts = {}
    # _switch = {"paleoData": "chronData", "chronData": "paleoData"}
    _pc = "paleoData"
    if mode == "chron":
        _pc = "chronData"
    _root["mode"] = _pc
    _root["time_id"] = time
    try:
        # Build the root level data.
        # This will serve as the template for which column data will be added onto later.
        for k, v in d.items():
            if k == "funding":
                _root = _extract_fund(v, _root)
            elif k == "geo":
                _root = _extract_geo(v, _root)
            elif k == 'pub':
                _root = _extract_pub(v, _root)
            # elif k in ["chronData", "paleoData"]:
            #     # Store chronData and paleoData as-is. Need it to collapse without data loss.
            #     _root[k] = copy.deepcopy(v)
            else:
                if k not in ["chronData", "paleoData"]:
                    _root[k] = v
        # Create tso dictionaries for each individual column (build on root data)
        _ts = _extract_pc(d, _root, _pc, whichtables)
    except Exception as e:
        logger_ts.error("extract: Exception: {}".format(e))
        print("extract: Exception: {}".format(e))

    logger_ts.info("exit extract_main")
    return _ts