code: def test_df_geojson_file_nonsequential_index(df):
      df.set_index("Avg Total Payments", inplace=True)
      features = df_to_geojson(df, filename="out.geojson")
      with open("out.geojson", "r") as f:
          testdata = json.load(f)
      assert len(testdata["features"]) == 3
  
imports: import os
  import json
  import numpy
  import pytest
  import pandas
  from pandas.util.testing import assert_frame_equal
  from matplotlib.pyplot import imread
  from mapboxgl.errors import SourceDataError, DateConversionError
  from mapboxgl.utils import df_to_geojson, geojson_to_dict_list, scale_between, create_radius_stops, create_weight_stops, create_numeric_stops, create_color_stops, img_encode, rgb_tuple_from_str, color_map, height_map, numeric_map, convert_date_columns
label_desc: Use image node_id 7 for calling a global function with example usage: test_df_geojson_file_nonsequential_index(df) without return types