code: def _choose_rest_version(self):
          
          versions = self._list_available_rest_versions()
          versions = [LooseVersion(x) for x in versions if x in self.supported_rest_versions]
          if versions:
              return max(versions)
          else:
              raise PureError(
                  "Library is incompatible with all REST API versions supported"
                  "by the target array.")
docs: Return the newest REST API version supported by target array.