code: def add_group_entitlement(self, group_entitlement, rule_option=None):
          
          query_parameters = {}
          if rule_option is not None:
              query_parameters['ruleOption'] = self._serialize.query('rule_option', rule_option, 'str')
          content = self._serialize.body(group_entitlement, 'GroupEntitlement')
          response = self._send(http_method='POST',
                                location_id='2280bffa-58a2-49da-822e-0764a1bb44f7',
                                version='5.0-preview.1',
                                query_parameters=query_parameters,
                                content=content)
          return self._deserialize('GroupEntitlementOperationReference', response)
docs: AddGroupEntitlement.
          [Preview API] Create a group entitlement with license rule, extension rule.
          :param :class:`<GroupEntitlement> <azure.devops.v5_0.member_entitlement_management.models.GroupEntitlement>` group_entitlement: GroupEntitlement object specifying License Rule, Extensions Rule for the group. Based on the rules the members of the group will be given licenses and extensions. The Group Entitlement can be used to add the group to another project level groups
          :param str rule_option: RuleOption [ApplyGroupRule/TestApplyGroupRule] - specifies if the rules defined in group entitlement should be created and applied to it’s members (default option) or just be tested
          :rtype: :class:`<GroupEntitlementOperationReference> <azure.devops.v5_0.member_entitlement_management.models.GroupEntitlementOperationReference>`