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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_users(self, envs=[], query="/users/"):
 """ List users in specified environments """

        juicer.utils.Log.log_debug(
                "List Users In: %s", ", ".join(envs))
        for env in envs:
            juicer.utils.Log.log_info("%s:" % (env))
            _r = self.connectors[env].get(query)
            if _r.status_code == Constants.PULP_GET_OK:
                for user in juicer.utils.load_json_str(_r.content):
                    roles = user['roles']
                    if roles:
                        user_roles = ', '.join(roles)
                    else:
                        user_roles = "None"
                    juicer.utils.Log.log_info("\t%s - %s" % (user['login'], user_roles))
            else:
                _r.raise_for_status()
        return True