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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, shorten=True):
 """Build the url for a broadcast ratings page"""

        url_order = self._get_url_params(shorten=shorten)

        # For fast ratings, switch weekday and category in url
        if self.category != 'final':
            url_order[1], url_order[2] = url_order[2], url_order[1]
        self.url = URL_FORMAT.format(*url_order)