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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_pages_binding(details):
 """ Parse number of pages and binding of the book. Args: details (obj):
 HTMLElement containing slice of the page with details. Returns: (pages, binding):
 Tuple with two string or two None. """

    pages = _get_td_or_none(
        details,
        "ctl00_ContentPlaceHolder1_tblRowRozsahVazba"
    )

    if not pages:
        return None, None

    binding = None  # binding info and number of pages is stored in same string
    if "/" in pages:
        binding = pages.split("/")[1].strip()
        pages = pages.split("/")[0].strip()

    if not pages:
        pages = None

    return pages, binding