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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_plugins(self):
 """ Attempts to load plugin modules according to the order of available plugin directories. """


        # import base plugin modules
        try:
            __import__('focus.plugin.modules')
            #import focus.plugin.modules
        except ImportError as exc:
            raise errors.PluginImport(unicode(exc))

        # load user defined plugin modules
        try:
            user_plugin_dir = os.path.join(self._data_dir, 'plugins')
            _import_modules(user_plugin_dir)

        except Exception as exc:
            raise errors.UserPluginImport(unicode(exc))