Hello Monks!

I have a file that contains multiple, very similar lines. How would I read through the file and remove every line in a block, except the very last one?

Example: 

Before ---
"SimpsonH","Homer","Simpson","NULL","648","0","218 555","Nuclear Contr
+ol","Nuclear Operator","SimpsonM"
"SimpsonH","Homer","Simpson","NULL","647","0","218 555","Nuclear Contr
+ol","Nuclear Operator","SimpsonM"
"SimpsonH","Homer","Simpson","NULL","648","0","218 555","Nuclear Contr
+ol","Nuclear Operator","BurnsM"
"SimpsonB","Bart","Simpson","NULL","748","0","218 555","Springfield El
+ementary","Student","SimpsonM"
"SimpsonB","Bart","Simpson","NULL","748","0","218 555","Springfield El
+ementary","Student","SimpsonH"
"SimpsonB","Bart","Simpson","NULL","748","1","218 555","Springfield El
+ementary","Student","SkinnerP"

After --
"SimpsonH","Homer","Simpson","NULL","648","0","218 555","Nuclear Contr
+ol","Nuclear Operator","SimpsonM"
"SimpsonB","Bart","Simpson","NULL","748","1","218 555","Springfield El
+ementary","Student","SkinnerP"

[download]

In reply to Removing multiple lines by rycher

Title:
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