code: def _get_best_row_for_single_objective(
      df: pd.DataFrame, objective: Objective
  ) -> pd.Series:
      objective_name = objective.metric.name
      objective_rows = df.loc[df["metric_name"] == objective_name]
      if objective_rows.empty:
          raise ValueError(
              f'No data has been logged for objective "{objective_name}".'
          )
      return (
          objective_rows.loc[objective_rows["mean"].idxmin()]
          if objective.minimize
          else objective_rows.loc[objective_rows["mean"].idxmax()]
      )
  
imports: from collections import OrderedDict
  from functools import reduce
  from logging import Logger
  from typing import Dict, Iterable, List, Optional, Tuple, Type
  import pandas
  import torch
  from ax.core.base_trial import TrialStatus
  from ax.core.batch_trial import BatchTrial
  from ax.core.data import Data
  from ax.core.experiment import Experiment
  from ax.core.generator_run import GeneratorRun
  from ax.core.objective import MultiObjective, Objective, ScalarizedObjective
  from ax.core.observation import Observation
  from ax.core.optimization_config import MultiObjectiveOptimizationConfig, OptimizationConfig
  from ax.core.outcome_constraint import ObjectiveThreshold, OutcomeConstraint
  from ax.core.trial import Trial
  from ax.core.types import ComparisonOp, TModelPredictArm, TParameterization
  from ax.exceptions.core import UnsupportedError, UserInputError
  from ax.modelbridge.base import ModelBridge
  from ax.modelbridge.cross_validation import assess_model_fit, compute_diagnostics, cross_validate
  from ax.modelbridge.generation_strategy import GenerationStrategy
  from ax.modelbridge.modelbridge_utils import observed_pareto_frontier, predicted_pareto_frontier
  from ax.modelbridge.registry import get_model_from_generator_run, ModelRegistryBase, Models
  from ax.modelbridge.torch import TorchModelBridge
  from ax.modelbridge.transforms.utils import derelativize_optimization_config_with_raw_status_quo
  from ax.plot.pareto_utils import get_tensor_converter_model
  from ax.utils.common.logger import get_logger
  from ax.utils.common.typeutils import checked_cast, not_none
  from numpy import NaN
  from torch import Tensor
label_desc: Use image node_id 13 for calling a global function with example usage: _get_best_row_for_single_objective(df, objective) and returns: unknown