code: def test_prepare_already_prepared():
      polygon = Polygon([(0, 0), (1, 0), (1, 1), (0, 1)])
      prepared = prep(polygon)
      # attempt to prepare an already prepared geometry with `prep`
      result = prep(prepared)
      assert isinstance(result, PreparedGeometry)
      assert result.context is polygon
      # attempt to prepare an already prepared geometry with `PreparedGeometry`
      result = PreparedGeometry(prepared)
      assert isinstance(result, PreparedGeometry)
      assert result.context is polygon
  
file_path: shapely/shapely/tests/legacy/test_prepared.py
imports: import numpy
  import pytest
  from shapely.geometry import Point, Polygon
  from shapely.prepared import prep, PreparedGeometry
label_desc: Use image node_id 6 for calling a global function with example usage: test_prepare_already_prepared() without return types