I usually use XML::XSH2 for XML manipulation. In this case, this script would make it:
open test.xml ;
set /students/student[id="002"]/gpa "B" ;
save :b ;

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In reply to Re: How can I replace a line (tag) in an XML file? by choroba
in thread How can I replace a line (tag) in an XML file? by perlPractioner

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