eZ\Publish\Core\REST\Client\RoleService::unassignRoleFromUserGroup PHP Method

    public function unassignRoleFromUserGroup(APIRole $role, UserGroup $userGroup)
    {
        $values = $this->requestParser->parse('group', $userGroup->id);
        $userGroupId = $values['group'];
        $values = $this->requestParser->parse('role', $role->id);
        $roleId = $values['role'];
        $response = $this->client->request('DELETE', $this->requestParser->generate('groupRoleAssignment', array('group' => $userGroupId, 'role' => $roleId)), new Message(array('Accept' => $this->outputVisitor->getMediaType('RoleAssignmentList'))));
        if (!empty($response->body)) {
            $this->inputDispatcher->parse($response);
        }
    }