code: def create_backend(
      self, project: ProjectModel, config: AWSConfigInfoWithCreds
  ) -> BackendModel:
      if config.regions is None:
          config.regions = DEFAULT_REGIONS
      return BackendModel(
          project_id=project.id,
          type=self.TYPE.value,
          config=AWSStoredConfig(
              **AWSConfigInfo.parse_obj(config).dict()
          ).json(),
          auth=AWSCreds.parse_obj(config.creds).json(),
      )
  
file_path: dstack/src/dstack/_internal/server/services/backends/configurators/aws.py
imports: import json
  from typing import List, Optional
  from dstack._internal.core.backends.aws import AWSBackend, auth
  from dstack._internal.core.backends.aws.config import AWSConfig
  from dstack._internal.core.errors import BackendAuthError
  from dstack._internal.core.models.backends.aws import AnyAWSConfigInfo, AWSAccessKeyCreds, AWSConfigInfo, AWSConfigInfoWithCreds, AWSConfigInfoWithCredsPartial, AWSConfigValues, AWSCreds, AWSDefaultCreds, AWSStoredConfig
  from dstack._internal.core.models.backends.base import BackendType, ConfigElementValue, ConfigMultiElement
  from dstack._internal.server import settings
  from dstack._internal.server.models import BackendModel, ProjectModel
  from dstack._internal.server.services.backends.configurators.base import Configurator, raise_invalid_credentials_error
label_desc: Use image node_id 3 for calling the AWSConfigurator obj's underlying member method code with example usage: obj.create_backend(project, config) and returns: BackendModel