def get_number_available(soup):
    """ Analyze "soup" to extract stock's availability.

    Args:
      soup -- bs4.BeautifulSoup from http request of book url.
    Return:
        stock's availability
    """
    table = soup.table
    cell = table.find_all("td")
    number_available = cell[5].text[10:-11]
  
    return int(number_available)