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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 _parse_publisher(details):
 """ Parse publisher of the book. Args: details (obj):
 HTMLElement containing slice of the page with details. Returns: str/None: Publisher's name as string or None if not found. """

    publisher = _get_td_or_none(
        details,
        "ctl00_ContentPlaceHolder1_tblRowNakladatel"
    )

    # publisher is not specified
    if not publisher:
        return None

    publisher = dhtmlparser.removeTags(publisher).strip()

    # return None instead of blank string
    if not publisher:
        return None

    return publisher