I created the isosurface with the short script below.

#!perl
use strict;
use Getopt::Long;
use MaterialsScript qw(:all);

my \$doc = \$Documents{"Cell.xsd"};
my \$result = Modules->DFTB->Energy->Run(\$doc, Settings(Quality => "Coarse",
SKFLibrary => "CHNO",
CalculateChargeDensity => "FieldAndIsosurface",
Smearing => "0.01",
));

# set field and parameter
my \$field = \$doc->AsymmetricUnit->Fields("DFTB+ total electron density");
my \$isosurface = \$field->Isosurface;
\$field->ColorMap->ColorMapMaxValue = \$field->FieldMax;
\$field->ColorMap->ColorMapMaxValue = \$field->FieldMin;
\$field->ColorMap->ColorMapColorSpectra = "Rainbow";
\$field->ColorMap->ColorMapNumberOfBands = 128;
\$field->ColorMap->ColorMapShowLegend = "Yes";
printf "%s IsHidden: %s\n", \$field->Name, \$field->IsHidden;

As a result, "printf "%s IsHidden: %s\n", \$field->Name, \$field->IsHidden;" is "DFTB+ total electron density IsHidden: 1".
How to "DFTB+ total electron density IsHidden: 0"??
If anyone knows about it, I would appreciate it if you could teach me.
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***append***
The pl file and xsd file used are as follows.

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