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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 render(self, route=None):
 """ Renders the application and returns the HTML unicode that would normally appear when visiting in the browser. """

        if route is None:
            route = '/'
        with self.test_client() as c:
            response = c.get(route, follow_redirects=True)
            encoding = response.charset
            return response.data.decode(encoding)