Prepares the container for loading ``mrc`` files by adding specfile
        entries to ``self.info``. Use :func:`MsrunContainer.load()` afterwards
        to actually import the files

        :param specfiles: the name of an ms-run file or a list of names
        :type specfiles: str or [str, str, ...]
        :param path: filedirectory used for loading and saving ``mrc`` files

def addSpecfile(self, specfiles, path):
        """Prepares the container for loading ``mrc`` files by adding specfile
        entries to ``self.info``. Use :func:`MsrunContainer.load()` afterwards
        to actually import the files

        :param specfiles: the name of an ms-run file or a list of names
        :type specfiles: str or [str, str, ...]
        :param path: filedirectory used for loading and saving ``mrc`` files
        """
        for specfile in aux.toList(specfiles):
            if specfile not in self.info:
                self._addSpecfile(specfile, path)
            else:
                warntext = 'Error while calling "MsrunContainer.addSpecfile()"'\
                           ': "%s" is already present "MsrunContainer.info"'\
                            % (specfile, )
                warnings.warn(warntext)