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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_syllabus(self, site):
 """ Gets the syllabus for a course. The syllabus may or may not contain HTML, depending on the site. TSquare does not enforce whether or not pages are allowed to have HTML, so it is impossible to tell. """

        tools = self.get_tools(site)
        syllabus_filter = [x.href for x in tools if x.name == 'syllabus']
        if not syllabus_filter:
            return ''
        response = self._session.get(syllabus_filter[0])
        response.raise_for_status()
        iframes = self._html_iface.get_iframes(response.text)
        iframe_url = ''
        for frame in iframes:
            if frame['title'] == 'Syllabus ':
                iframe_url = frame['src']
        if iframe_url == '':
            print "WARHING: NO SYLLABUS IFRAME FOUND"
        response = self._session.get(iframe_url)
        response.raise_for_status()
        syllabus_html = self._html_iface.get_syllabus(response.text)
        return syllabus_html