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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_config(self):
 """List all of the configuration variables """

        items = self.kvstore.get_all()
        return ["{0}={1}".format(x[0][len('config:'):], x[1])
                for x in items if x[0].startswith('config:')]