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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 make_ring_filename(self, source_name, ring, galprop_run):
 """ Make the name of a gasmap file for a single ring Parameters source_name : str The galprop component, used to define path to gasmap files ring : int The ring index galprop_run : str String identifying the galprop parameters """

        format_dict = self.__dict__.copy()
        format_dict['sourcekey'] = self._name_factory.galprop_ringkey(source_name=source_name,
                                                                      ringkey="ring_%i" % ring)
        format_dict['galprop_run'] = galprop_run
        return self._name_factory.galprop_gasmap(**format_dict)