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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 load_content(self):
 """ Load the book content """


        # get the toc file from the root file
        rel_path = self.root_file_url.replace(os.path.basename(self.root_file_url), '')
        self.toc_file_url = rel_path + self.root_file.find(id="ncx")['href']
        self.toc_file_soup = bs(self.book_file.read(self.toc_file_url), 'xml')

        # get the book content from the toc file

        for n, c in cross(self.toc_file_soup.find_all('navLabel'), self.toc_file_soup.find_all('content')):
            content_soup = bs(self.book_file.read(rel_path + c.get('src')))
            self.content.append({'part_name': c.text,
                                 'source_url': c.get('src'),
                                 'content_source': content_soup,
                                 'content_source_body': content_soup.body,
                                 'content_source_text': content_soup.body.text})