Adding useful columns

mods4pandas tries to stay close to the data it converts. For example, this means that there is no such column as "fulltext available", but there is statistical information about the METS file groups used for the work. So to add a column that tells us if a fulltext is available, given that the METS file group FULLTEXT exists, one needs to create the column when working with the data:

mods_info_df["fulltext available"] = mods_info_df["mets_fileSec_fileGrp-FULLTEXT-count"].notna()