code: def gatk_type(self):
          
          if LooseVersion(self.gatk_major_version()) > LooseVersion("3.9"):
              return "gatk4"
          elif LooseVersion(self.gatk_major_version()) > LooseVersion("2.3"):
              return "restricted"
          else:
              return "lite"
docs: Retrieve type of GATK jar, allowing support for older GATK lite.
          Returns either `lite` (targeting GATK-lite 2.3.9) or `restricted`,
          the latest 2.4+ restricted version of GATK.