Regex
Bulk Renaming Utility is used. May not work somewhere else, unless you add the necessary flags.
(_){0,}(.*)
2 Groups, group one catches an underscore, group one is repeated 0 to an unlimited times {0,}
to capture all underscores before group 2 starts (.*)
. Group 2 captures all characters.
Then we replace the string by the result of goup 2 only \2
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