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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 get_nanopubstore_start_dt(url: str):
 """Get last start_dt recorded for getting new nanopub ID's"""


    hostname = urllib.parse.urlsplit(url)[1]

    start_dates_doc = state_mgmt.get(start_dates_doc_key)
    if start_dates_doc and start_dates_doc.get("start_dates"):
        date = [
            dt["start_dt"]
            for dt in start_dates_doc["start_dates"]
            if dt["nanopubstore"] == hostname
        ]
        log.info(f"Selected start_dt: {date}  len: {len(date)}")
        if len(date) == 1:
            return date[0]

    return "1900-01-01T00:00:00.000Z"