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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_ISBN_EAN(details):
 """ Parse ISBN and EAN. Args: details (obj):
 HTMLElement containing slice of the page with details. Returns: (ISBN, EAN):
 Tuple with two string or two None. """

    isbn_ean = _get_td_or_none(
        details,
        "ctl00_ContentPlaceHolder1_tblRowIsbnEan"
    )

    if not isbn_ean:
        return None, None

    ean = None
    isbn = None
    if "/" in isbn_ean:  # ISBN and EAN are stored in same string
        isbn, ean = isbn_ean.split("/")
        isbn = isbn.strip()
        ean = ean.strip()
    else:
        isbn = isbn_ean.strip()

    if not isbn:
        isbn = None

    return isbn, ean