The shebang says to which executable to feed the script, so for a perl script, it's simply:

#!/usr/bin/perl
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You can add options if you like:

#!/usr/bin/perl -w
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If you're trying to feed another script to your own script, you have to do #!/usr/bin/perl /usr/bin/perl/myscript.pl instead of #!/usr/bin/perl/myscript.pl because myscript.pl is not an executable.