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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 dispatch(self, *args, **kwargs):
 """ Check that user signup is allowed before even bothering to dispatch or do other processing. """

        if not self.registration_allowed():
            return HttpResponseRedirect(force_text(self.disallowed_url))
        return super(RegistrationView, self).dispatch(*args, **kwargs)