code: def __draw_parity_test_explanation(
      fairness_threshold, x_position, warnings=()
  ):
      """Draw text that explains what does pass/fail mean in the parity test results."""
      text_explanation = []
  
      warn_text = alt.Chart(DUMMY_DF).mark_text(
          baseline="top",
          align="left",
          font=FONT,
          fill="rgb(211, 47, 47)",
          fontSize=Annotation.font_size,
          fontWeight=Annotation.font_weight,
      )
  
      explanation_text = alt.Chart(DUMMY_DF).mark_text(
          baseline="top",
          align="left",
          font=FONT,
          fill=Annotation.font_color,
          fontSize=Annotation.font_size,
          fontWeight=Annotation.font_weight,
      )
  
      n_warnings = 0
      for metric_warnings in warnings:
          if metric_warnings:
              for group, metric in metric_warnings:
                  explanation_text_warning = warn_text.encode(
                      x=alt.value(x_position),
                      y=alt.value(
                          Annotation.font_size
                          * Annotation.line_spacing
                          * (n_warnings + 2)
                      ),
                      text=alt.value(
                          f"Groups {group} have {metric} of 0 (zero). This "
                          "does not allow for the calculation of relative disparities. "
                          "The groups will be absent in respective visualizations.",
                      ),
                  )
                  n_warnings += 1
                  text_explanation.append(explanation_text_warning)
  
      explanation_text_group = explanation_text.encode(
          x=alt.value(x_position),
          y=alt.value(0),
          text=alt.value(
              f"For a group to pass the parity test its disparity to the reference group cannot exceed the fairness threshold ({fairness_threshold})."
          ),
      )
  
      explanation_text_attribute = explanation_text.encode(
          x=alt.value(x_position),
          y=alt.value(Annotation.font_size * Annotation.line_spacing),
          text=alt.value(
              f"An attribute passes the parity test for a given metric if all its groups pass the test."
          ),
      )
      text_explanation.append(explanation_text_group)
      text_explanation.append(explanation_text_attribute)
      return alt.layer(*(chart for chart in text_explanation))
  
imports: import altair
  import pandas
  from aequitas.plot.commons.helpers import no_axis, transform_ratio, format_number, get_chart_metadata
  from aequitas.plot.commons.tooltips import get_tooltip_text_group_size, get_tooltip_text_disparity_explanation, get_tooltip_text_parity_test_explanation
  from aequitas.plot.commons.style.classes import Title, Subtitle, Parity_Result, Annotation, Legend
  from aequitas.plot.commons.style.text import FONT
  from aequitas.plot.commons.style.sizes import Summary_Chart
  from aequitas.plot.commons import initializers
  from aequitas.plot.commons import validators
  from aequitas.plot.commons import labels
label_desc: Use image node_id 9 for calling a global function with example usage: __draw_parity_test_explanation(fairness_threshold, x_position, warnings) and returns: alt