Unregisters given file in the **file_system_events_manager**.

        :param file: File.
        :type file: unicode
        :return: Method success.
        :rtype: bool

def unregister_file(self, file):
        """
        Unregisters given file in the **file_system_events_manager**.

        :param file: File.
        :type file: unicode
        :return: Method success.
        :rtype: bool
        """

        self.__engine.file_system_events_manager.is_path_registered(file) and \
        self.__engine.file_system_events_manager.unregister_path(file)
        return True