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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

from __future__ import absolute_import
import json
from ansible.module_utils.urls import fetch_url
try:
    from urllib import quote_plus  
except ImportError:
    from urllib.parse import quote_plus  
def request(module, api_url, project, path, access_token, private_token, rawdata='', method='GET'):
    url = "%s/v4/projects/%s%s" % (api_url, quote_plus(project), path)
    headers = {}
    if access_token:
        headers['Authorization'] = "Bearer %s" % access_token
    else:
        headers['Private-Token'] = private_token
    headers['Accept'] = "application/json"
    headers['Content-Type'] = "application/json"
    response, info = fetch_url(module=module, url=url, headers=headers, data=rawdata, method=method)
    status = info['status']
    content = ""
    if response:
        content = response.read()
    if status == 204:
        return True, content
    elif status == 200 or status == 201:
        return True, json.loads(content)
    else:
        return False, str(status) + ": " + content
def findProject(gitlab_instance, identifier):