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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_price(html_chunk):
 """ Parse price of the book. Args: html_chunk (obj):
 HTMLElement containing slice of the page with details. Returns: str/None: Price as string with currency or None if not found. """

    price = get_first_content(
        html_chunk.find("div", {"class": "prices"})
    )

    if not price:
        return None

    # it is always in format Cena:\n150kč
    price = dhtmlparser.removeTags(price)
    price = price.split("\n")[-1]

    return price