code: def test_read_topojson(data_dir):
      """Test reading a TopoJSON file
  
      The TopoJSON support in GDAL is a little unpredictable. In some versions
      the geometries or properties aren't parsed correctly. Here we just check
      that we can open the file, get the right number of features out, and
      that they have a geometry and some properties. See GH#722.
      """
      with fiona.open(
          os.path.join(data_dir, "example.topojson"), "r"
      ) as collection:
          features = list(collection)
  
      assert len(features) == 3, "unexpected number of features"
      for feature in features:
          assert isinstance(feature["properties"], Properties)
          assert len(feature["properties"]) > 0
          assert feature["geometry"]["type"] in {
              "Point",
              "LineString",
              "Polygon",
          }
  
imports: import os
  import pytest
  import fiona
  from fiona.env import GDALVersion
  from fiona.model import Properties
label_desc: Use image node_id 1 for calling a global function with example usage: test_read_topojson(data_dir) without return types