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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_redirect_url(self, request, callback, parameters=None):
 """Build authentication redirect url."""

        args = self.get_redirect_args(request, callback=callback)
        additional = parameters or {}
        args.update(additional)
        params = urlencode(args)
        return '{0}?{1}'.format(self.authorization_url, params)