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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 load_conf_modules():
 """Load all modules that contain configuration. Method iterates over modules of :py:module:`monasca_persister.conf` and imports only those that contain following methods: - list_opts (required by oslo_config.genconfig) - register_opts (required by :py:currentmodule:) """

    for modname in _list_module_names():
        mod = importutils.import_module('monasca_persister.conf.' + modname)
        required_funcs = ['register_opts', 'list_opts']
        for func in required_funcs:
            if hasattr(mod, func):
                yield mod