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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

key=dict(type='str', required=True),
        can_push=dict(type='bool', default=False),
        title=dict(type='str', required=True)
    ))
    module = AnsibleModule(
        argument_spec=argument_spec,
        mutually_exclusive=[
            ['api_username', 'api_token'],
            ['api_password', 'api_token']
        ],
        required_together=[
            ['api_username', 'api_password']
        ],
        required_one_of=[
            ['api_username', 'api_token']
        ],
        supports_check_mode=True,
    )
    gitlab_url = re.sub('/api.*', '', module.params['api_url'])
    validate_certs = module.params['validate_certs']
    gitlab_user = module.params['api_username']
    gitlab_password = module.params['api_password']
    gitlab_token = module.params['api_token']
    state = module.params['state']
    project_identifier = module.params['project']
    key_title = module.params['title']
    key_keyfile = module.params['key']
    key_can_push = module.params['can_push']
    if not HAS_GITLAB_PACKAGE:
        module.fail_json(msg=missing_required_lib("python-gitlab"), exception=GITLAB_IMP_ERR)