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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 _discover_models(self):
 """ Return a dict containing a list of cassandra.cqlengine.Model classes within installed App. """


        apps = get_installed_apps()
        connection = self.connection.connection.alias
        keyspace = self.connection.connection.keyspace

        for app in apps:
            self._cql_models[app.__name__] = get_cql_models(
                app, connection=connection, keyspace=keyspace)