code: def test_ratio_errors_ones(example_diversity_ones_zeros):
      y, y_pred_ones, y_pred_zeros = example_diversity_ones_zeros
      ratio = ratio_errors(y, y_pred_ones, y_pred_ones)
      assert ratio == 0.0
  
imports: import sys
  import numpy
  import pytest
  from deslib.util.diversity import _process_predictions, double_fault, Q_statistic, ratio_errors, agreement_measure, disagreement_measure, correlation_coefficient
label_desc: Use image node_id 17 for calling a global function with example usage: test_ratio_errors_ones(example_diversity_ones_zeros) without return types