docs: def _pyxb_from_norm_perm_list(self, norm_perm_list):
          """Return an AccessPolicy PyXB representation of ``norm_perm_list``"""
          # Using accessPolicy() instead of AccessPolicy() and accessRule() instead of
          # AccessRule() gives PyXB the type information required for using this as a
          # root element.
          access_pyxb = d1_common.types.dataoneTypes.accessPolicy()
          for perm_str, subj_list in norm_perm_list:
              rule_pyxb = d1_common.types.dataoneTypes.accessRule()
              rule_pyxb.permission.append(perm_str)
              for subj_str in subj_list:
                  rule_pyxb.subject.append(subj_str)
              access_pyxb.allow.append(rule_pyxb)
          if len(access_pyxb.allow):
              return access_pyxb