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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 extract_js_links(bs4):
 """Extracting js links from BeautifulSoup object :param bs4: `BeautifulSoup` :return: `list` List of links """


    links = extract_links(bs4)

    real_js = [anchor for anchor in links if anchor.endswith(('.js', '.JS'))]

    js_tags = [anchor['src'] for anchor in bs4.select('script[type="text/javascript"]')
               if anchor.has_attr('src')]

    return list(set(real_js+js_tags))