code: def create_backend(
      self, project: ProjectModel, config: NebiusConfigInfoWithCreds
  ) -> BackendModel:
      if config.regions is None:
          config.regions = REGIONS
      self._validate_nebius_creds(config.creds)
      return BackendModel(
          project_id=project.id,
          type=self.TYPE.value,
          config=NebiusStoredConfig.parse_obj(config).json(),
          auth=NebiusCreds.parse_obj(config.creds).json(),
      )
  
imports: import json
  from typing import List
  import requests
  import dstack._internal.core.backends.nebius.api_client
  from dstack._internal.core.backends.base import Backend
  from dstack._internal.core.backends.nebius import NebiusBackend
  from dstack._internal.core.backends.nebius.config import NebiusConfig
  from dstack._internal.core.models.backends.base import BackendType, ConfigElementValue, ConfigMultiElement
  from dstack._internal.core.models.backends.nebius import NebiusConfigInfo, NebiusConfigInfoWithCreds, NebiusConfigInfoWithCredsPartial, NebiusConfigValues, NebiusCreds, NebiusStoredConfig
  from dstack._internal.server.models import BackendModel, ProjectModel
  from dstack._internal.server.services.backends import Configurator
  from dstack._internal.server.services.backends.configurators.base import raise_invalid_credentials_error
label_desc: Use image node_id 3 for calling the NebiusConfigurator obj's underlying member method code with example usage: obj.create_backend(project, config) and returns: BackendModel