I want to UPPERcase the last 2 letters

I want to UPPERcase the last 2 letters only.

EXAMPLE:         Test NAME Siren.txt
EXPRESSION:   %lb(1,-2)%ub(-2,).*
RESULT:           test name sirEN.txt

EXPLANATIONS:

%lb(1,-2)%ub(-2,).*

%lb      lower case all chars of the base file name
(1,-2)   but only the char from the begin to the second last char

Test NAME Siren         the hole name
1                               the start at position 1
----------------21         till position 2 from the right

%ub   upper case all chars of the base file name
(-2,)   but start at the second char from the right, till the end
.         the dot between file name and extension
*        the extension (in this case because it's on the right side of the dot)

Press the F1-key while you are in Siren to read more about.
Enjoy Siren,  No installation needed, unzip and run. Siren stores it settings into an ini file.
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