code: def test_stereographic():
      crs = ProjectedCRS(conversion=StereographicConversion(0, 1, 2, 3))
      expected_cf = {
          "semi_major_axis": 6378137.0,
          "semi_minor_axis": crs.ellipsoid.semi_minor_metre,
          "inverse_flattening": crs.ellipsoid.inverse_flattening,
          "reference_ellipsoid_name": "WGS 84",
          "longitude_of_prime_meridian": 0.0,
          "prime_meridian_name": "Greenwich",
          "horizontal_datum_name": "World Geodetic System 1984 ensemble",
          "grid_mapping_name": "stereographic",
          "latitude_of_projection_origin": 0.0,
          "longitude_of_projection_origin": 1.0,
          "false_easting": 2.0,
          "false_northing": 3.0,
          "scale_factor_at_projection_origin": 1.0,
          "geographic_crs_name": "undefined",
          "projected_crs_name": "undefined",
      }
      cf_dict = crs.to_cf()
      assert cf_dict.pop("crs_wkt").startswith("PROJCRS[")
      assert cf_dict == expected_cf
      # test roundtrip
      _test_roundtrip(expected_cf, "PROJCRS[")
      # test coordinate system
      assert crs.cs_to_cf() == [
          {
              "axis": "X",
              "long_name": "Easting",
              "standard_name": "projection_x_coordinate",
              "units": "metre",
          },
          {
              "axis": "Y",
              "long_name": "Northing",
              "standard_name": "projection_y_coordinate",
              "units": "metre",
          },
      ]
  
imports: import numpy
  import pytest
  from numpy.testing import assert_almost_equal
  from packaging import version
  from pyproj import CRS
  from pyproj.crs import ProjectedCRS
  from pyproj.crs._cf1x8 import _try_list_if_string
  from pyproj.crs.coordinate_operation import LambertAzimuthalEqualAreaConversion, LambertCylindricalEqualAreaConversion, MercatorAConversion, OrthographicConversion, PolarStereographicAConversion, PolarStereographicBConversion, SinusoidalConversion, StereographicConversion, VerticalPerspectiveConversion
  from pyproj.exceptions import CRSError
  from test.conftest import PROJ_GTE_901, PROJ_LOOSE_VERSION
label_desc: Use image node_id 35 for calling a global function with example usage: test_stereographic() without return types