DeletePullRequestLabels.
        [Preview API] Removes a label from the set of those assigned to the pull request.
        :param str repository_id: The repository ID of the pull request’s target branch.
        :param int pull_request_id: ID of the pull request.
        :param str label_id_or_name: The name or ID of the label requested.
        :param str project: Project ID or project name
        :param str project_id: Project ID or project name.

def delete_pull_request_labels(self, repository_id, pull_request_id, label_id_or_name, project=None, project_id=None):
        """DeletePullRequestLabels.
        [Preview API] Removes a label from the set of those assigned to the pull request.
        :param str repository_id: The repository ID of the pull request’s target branch.
        :param int pull_request_id: ID of the pull request.
        :param str label_id_or_name: The name or ID of the label requested.
        :param str project: Project ID or project name
        :param str project_id: Project ID or project name.
        """
        route_values = {}
        if project is not None:
            route_values['project'] = self._serialize.url('project', project, 'str')
        if repository_id is not None:
            route_values['repositoryId'] = self._serialize.url('repository_id', repository_id, 'str')
        if pull_request_id is not None:
            route_values['pullRequestId'] = self._serialize.url('pull_request_id', pull_request_id, 'int')
        if label_id_or_name is not None:
            route_values['labelIdOrName'] = self._serialize.url('label_id_or_name', label_id_or_name, 'str')
        query_parameters = {}
        if project_id is not None:
            query_parameters['projectId'] = self._serialize.query('project_id', project_id, 'str')
        self._send(http_method='DELETE',
                   location_id='f22387e3-984e-4c52-9c6d-fbb8f14c812d',
                   version='5.1-preview.1',
                   route_values=route_values,
                   query_parameters=query_parameters)