see Trusted and Untrusted PL/Perl

I was able to get this to work using plperlu after running CREATE EXTENSION plperlu;

CREATE OR REPLACE FUNCTION get(character varying)
  RETURNS json AS
$BODY$
use warnings;
use strict;
use LWP::Simple;
my $content = get($_[0]);
$content =~ s/ /%20/g;
return $content;
 
$BODY$
  LANGUAGE plperlu VOLATILE
  COST 100;
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