code: def get_abstention_rate(self) -> np.ndarray:
      df = pd.read_csv(self.data_file_path, delimiter="\t")
      return (
          1.0 * (df["predict"] == -1).sum() / len(df["predict"]) * 100
      )
  
imports: from easydict import EasyDict
  from typing import *
  import math
  import matplotlib
  import matplotlib.pyplot
  import numpy
  import os
  import pandas
  import seaborn
label_desc: Use image node_id 4 for calling the ApproximateAccuracy obj's underlying member method code with example usage: obj.get_abstention_rate() and returns: unknown