code: def get_instance(
      cls,
      datasets: DatasetsService = Depends(DatasetsService.get_instance),
      metrics: MetricsService = Depends(MetricsService.get_instance),
  ):
      if not cls._INSTANCE:
          cls._INSTANCE = cls(datasets, metrics=metrics)
      return cls._INSTANCE
  
file_path: argilla/src/argilla/server/apis/v0/validators/text_classification.py
imports: from typing import List, Optional, Set
  from fastapi import Depends
  from argilla.server.apis.v0.models.dataset_settings import TextClassificationSettings
  from argilla.server.errors import BadRequestError, EntityNotFoundError
  from argilla.server.models import User
  from argilla.server.schemas.v0.datasets import Dataset
  from argilla.server.services.datasets import DatasetsService
  from argilla.server.services.metrics import MetricsService
  from argilla.server.services.tasks.text_classification.metrics import DatasetLabels
  from argilla.server.services.tasks.text_classification.model import ServiceTextClassificationRecord
label_desc: Use image node_id 2 for calling the DatasetValidator obj's underlying member method code with example usage: obj.get_instance(cls, datasets, metrics) and returns: cls