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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_klass(self):
 """ Return the agnocomplete class to be used with the eventual query. """

        # Extract the klass name from the URL arguments
        klass_name = self.kwargs.get('klass', None)
        klass = self.registry.get(klass_name, None)
        if not klass:
            raise Http404("Unknown autocomplete class `{}`".format(klass_name))
        return klass