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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

def __init__(self, module, gitlab_instance):
        self.repo = gitlab_instance
        self.project = self.get_project(module.params['project'])
        self._module = module
    def get_project(self, project_name):
        return self.repo.projects.get(project_name)
    def list_all_project_variables(self):
        return self.project.variables.list()
    def create_variable(self, key, value):
        if self._module.check_mode:
            return
        return self.project.variables.create({"key": key, "value": value})
    def update_variable(self, var, value):