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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 list_catalogs(self):
 """ Lists existing catalogs respect to ui view template format """

        _form = CatalogSelectForm(current=self.current)
        _form.set_choices_of('catalog', [(i, i) for i in fixture_bucket.get_keys()])
        self.form_out(_form)