The parameter --model of DetermineGermlineContigPloidy when use CASE mode

When I use DetermineGermlineContigPloidy about CASE mode:
```
gatk DetermineGermlineContigPloidy \
--model a_valid_ploidy_model_dir
--input normal_1.counts.hdf5 \
--input normal_2.counts.hdf5 \
... \
--output output_dir \
--output-prefix normal_case
```
How can I get this file ' a_valid_ploidy_model_dir', or generate it ? Is there some command line do it ?