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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_modules(self, modules, config):
 """Load plugin modules."""

        for pluginclass in get_plugin_classes(modules):
            name = pluginclass.__name__
            if name in config["enabledplugins"]:
                if issubclass(pluginclass, _ConnectionPlugin):
                    log.debug(LOG_PLUGIN, "Enable connection plugin %s", name)
                    self.connection_plugins.append(pluginclass(config[name]))
                elif issubclass(pluginclass, _ContentPlugin):
                    log.debug(LOG_PLUGIN, "Enable content plugin %s", name)
                    self.content_plugins.append(pluginclass(config[name]))
                elif issubclass(pluginclass, _ParserPlugin):
                    log.debug(LOG_PLUGIN, "Enable parser plugin %s", name)
                    self.parser_plugins.append(pluginclass(config[name]))
                else:
                    raise ValueError("Invalid plugin class %s" % pluginclass)