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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 build_url(self):
 """Build appropiate encoded URL. This implies the same way of searching a torrent as in the page itself. """

        url = requests.utils.requote_uri(
            self.torrent_page + self.string_search)
        if self.page == '1337x':
            return(url + '/1/')
        elif self.page == 'limetorrents':
            return(url + '/')
        else:
            return(url)