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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 deactivate(self, plugins=[]):
 """ Deactivates given plugins. A given plugin must be activated, otherwise it is ignored and no action takes place (no signals are fired, no deactivate functions are called.) A deactivated plugin is still loaded and initialised and can be reactivated by calling :func:`activate` again. It is also still registered in the :class:`.PluginManager` and can be requested via :func:`get`. :param plugins: List of plugin names :type plugins: list of strings """

        self._log.debug("Plugins Deactivation started")

        if not isinstance(plugins, list):
            raise AttributeError("plugins must be a list, not %s" % type(plugins))

        self._log.debug("Plugins to deactivate: %s" % ", ".join(plugins))

        plugins_deactivated = []
        for plugin_name in plugins:
            if not isinstance(plugin_name, str):
                raise AttributeError("plugin name must be a str, not %s" % type(plugin_name))

            if plugin_name not in self._plugins.keys():
                self._log.info("Unknown activated plugin %s" % plugin_name)
                continue
            else:
                self._log.debug("Deactivating plugin %s" % plugin_name)
                if not self._plugins[plugin_name].active:
                    self._log.warning("Plugin %s seems to be already deactivated" % plugin_name)
                else:
                    try:
                        self._plugins[plugin_name].deactivate()
                    except Exception as e:
                        raise_from(
                            PluginNotDeactivatableException("Plugin %s could not be deactivated" % plugin_name), e)
                    else:
                        self._log.debug("Plugin %s deactivated" % plugin_name)
                        plugins_deactivated.append(plugin_name)

        self._log.info("Plugins deactivated: %s" % ", ".join(plugins_deactivated))