code: def test_shortest_line_empty(prepare):
      g1 = _prepare_input(line_string, prepare)
      assert shapely.shortest_line(g1, empty_line_string) is None
      g1_empty = _prepare_input(empty_line_string, prepare)
      assert shapely.shortest_line(g1_empty, line_string) is None
      assert shapely.shortest_line(g1_empty, empty_line_string) is None
  
imports: import numpy
  import pytest
  import shapely
  from shapely import GeometryCollection, LinearRing, LineString, MultiLineString, Point
  from shapely.errors import UnsupportedGEOSVersionError
  from shapely.testing import assert_geometries_equal
  from shapely.tests.common import empty_line_string, empty_point, line_string, linear_ring, multi_line_string, multi_point, multi_polygon, point, polygon
label_desc: Use image node_id 22 for calling a global function with example usage: test_shortest_line_empty(prepare) without return types