Glances API RESTful implementation.

        Return the JSON representation of the Glances command line arguments item
        HTTP/200 if OK
        HTTP/400 if item is not found
        HTTP/404 if others error

def _api_args_item(self, item):
        """Glances API RESTful implementation.

        Return the JSON representation of the Glances command line arguments item
        HTTP/200 if OK
        HTTP/400 if item is not found
        HTTP/404 if others error
        """
        response.content_type = 'application/json; charset=utf-8'

        if item not in self.args:
            abort(400, "Unknown argument item %s" % item)

        try:
            # Get the JSON value of the args' dict
            # Use vars to convert namespace to dict
            # Source: https://docs.python.org/%s/library/functions.html#vars
            args_json = json.dumps(vars(self.args)[item])
        except Exception as e:
            abort(404, "Cannot get args item (%s)" % str(e))
        return args_json