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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

if var.value == value:
            return False
        if self._module.check_mode:
            return True
        var.value = value
        var.save()
        return True
    def delete_variable(self, key):
        if self._module.check_mode:
            return
        return self.project.variables.delete(key)
def native_python_main(this_gitlab, purge, var_list, state):
    change = False
    return_value = dict(added=list(), updated=list(), removed=list(), untouched=list())
    gitlab_keys = this_gitlab.list_all_project_variables()
    existing_variables = [x.get_id() for x in gitlab_keys]
    for key in var_list:
        if key in existing_variables:
            index = existing_variables.index(key)
            existing_variables[index] = None
            if state == 'present':
                single_change = this_gitlab.update_variable(
                    gitlab_keys[index], var_list[key])
                change = single_change or change
                if single_change:
                    return_value['updated'].append(key)
                else:
                    return_value['untouched'].append(key)
            elif state == 'absent':