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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 get_genres(self):
 """ Grab genre URLs from iTunes Podcast preview """

    page = r.get(ITUNES_GENRES_URL)
    tree = html.fromstring(page.content)
    elements = tree.xpath("//a[@class='top-level-genre']")
    return [e.attrib['href'] for e in elements]