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##### SUMMARY
<!--- Explain the problem briefly below -->

`python-gitlab` library release a new version [v1.13.0](https://github.com/python-gitlab/python-gitlab/releases/tag/v1.13.0). User/Password authentication as been removed completely causing all Ansible GitLab module to fail... 

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->

gitlab_group
gitlab_deploy_key
gitlab_hook
gitlab_project
gitlab_project_variable
gitlab_runner
gitlab_user

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
All versions

group = findGroup(self._gitlab, group_identifier)
        if self._module.check_mode:
            return True
        if group is None:
            return False
        if self.memberExists(group, self.getUserId(user)):
            member = self.findMember(group, self.getUserId(user))
            if not self.memberAsGoodAccessLevel(group, member.id, self.ACCESS_LEVEL[access_level]):
                member.access_level = self.ACCESS_LEVEL[access_level]
                member.save()
                return True
        else:
            try:
                group.members.create({
                    'user_id': self.getUserId(user),
                    'access_level': self.ACCESS_LEVEL[access_level]})
            except gitlab.exceptions.GitlabCreateError as e:
                self._module.fail_json(msg="Failed to assign user to group: %s" % to_native(e))
            return True
        return False
    '''
    @param user User object
    @param arguments User attributes
    '''
    def updateUser(self, user, arguments):