my %hashvariable;
@hashvariable{@variable} = @vardescription;
my $TestText;

{
	local $/;
	open( my $in, '<', "Test.txt" ) or die "cannot open Test.txt $!";
	my $TestText = <$in>;
	close $in;
}

$TestText =~ s/$_/$hashvariable{$_}/g for keys %hashvariable;

open( my $out, '>', "TestFinal.txt" ) or die "cannot create TestFinal $!";
print $out $TestText;
close $out;