@zlm The .po file just there so we can view it. The actually used file is the .mo file. So, simple editing the po file would not work. For this you need to download Poedit software http://www.poedit.net/. After you install this software open the .po file with this software, make the changes and save the file. After you do this automatically the .mo (the binary file) will also have the corresponding changes. Try this.
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