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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):
        '''
        Sets up all plugins and defaults
        '''
        plugins = self.settings['PLUGINS']

        self.plugins_dict = {}
        for key in plugins:
            # skip loading the plugin if its value is None
            if plugins[key] is None:
                continue
            # valid plugin, import and setup
            self.logger.debug("Trying to load plugin {cls}"
                              .format(cls=key))
            the_class = self.import_class(key)
            instance = the_class()
            instance.redis_conn = self.redis_conn
            instance._set_logger(self.logger)
            if not self.unit_test:
                instance.setup(self.settings)
            the_regex = instance.regex

            mini = {}
            mini['instance'] = instance
            if the_regex is None:
                raise ImportError()
                # continue
            mini['regex'] = the_regex

            self.plugins_dict[plugins[key]] = mini

        self.plugins_dict = OrderedDict(sorted(list(self.plugins_dict.items()),
                                               key=lambda t: t[0]))