Try it out yourself. Create a script like so:

print "Hello\n";
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Put it in a file named hello.pl and run this (untested):

print "1: ", join ', ', %INC, "\n";
do 'hello.pl';
print "2: ", join ', ', %INC, "\n";
use Data::Dumper;
print "3: ", join ', ', %INC, "\n";
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