To find out if a module is installed on your system, try typing the following at a shell prompt:

perl -M'[module name]' -V
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This will print something starting like:

Summary of my perl5 (5.0 patchlevel 5 subversion 3) configuration:
....
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If the module is installed, or:

Can't locate [module name] in @INC (@INC contains: /usr/lib/perl5/5.00
+5/i386-linux /usr/lib/perl5/5.005 /usr/local/lib/site_perl/i386-linux
+ /usr/local/lib/site_perl /usr/lib/perl5 .).
BEGIN failed--compilation aborted.
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If it isn't.