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##### SUMMARY
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`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

try:
            member = group.members.get(user_id)
        except gitlab.exceptions.GitlabGetError:
            return None
        return member
    '''
    @param group Group object
    @param user_id Id of the user to check
    '''
    def memberExists(self, group, user_id):
        member = self.findMember(group, user_id)
        return member is not None
    '''
    @param group Group object
    @param user_id Id of the user to check
    @param access_level GitLab access_level to check
    '''
    def memberAsGoodAccessLevel(self, group, user_id, access_level):
        member = self.findMember(group, user_id)
        return member.access_level == access_level
    '''
    @param user User object
    @param group_path Complete path of the Group including parent group path. <parent_path>/<group_path>
    @param access_level GitLab access_level to assign
    '''
    def assignUserToGroup(self, user, group_identifier, access_level):