I would like to use regex to remove underscores from multiple files name.

But i encountered a problem

For eg I came across two files name as follows


file1 = Hello_World

file2 = Hello_World_

I would like to remove the last underscore in file2 to get Hello_world but i would like to keep file1 as it is. How do i do so?

i have tried s/_/$1/ but it doesn't works.

In reply to Regex help by Anonymous Monk

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