The "remove()" function is obsolete, you need to change it to "ent_remove()".

Open sed, do a "find text in files", select the folder you have the files in
and search for "remove", it should find several occurences. click on the first
one and sed will open the file with the occurance at the top, change it
to "ent_remove" by adding "ent_",. do this with all occurances, then save all
the files you modified before closing them. Should run fine then.