code: def test_build_custom_datum():
      cf_dict = {
          "semi_major_axis": 6370997.0,
          "semi_minor_axis": 6370997.0,
          "inverse_flattening": 0.0,
          "reference_ellipsoid_name": "Normal Sphere (r=6370997)",
          "longitude_of_prime_meridian": 1.0,
          "grid_mapping_name": "oblique_mercator",
          "latitude_of_projection_origin": 0.0,
          "longitude_of_projection_origin": 13.809602948622212,
          "azimuth_of_central_line": 8.998112717187938,
          "scale_factor_at_projection_origin": 1.0,
          "false_easting": 0.0,
          "false_northing": 0.0,
      }
      crs = CRS.from_cf(cf_dict)
      assert crs.datum.name == "undefined"
      assert crs.ellipsoid.name == "Normal Sphere (r=6370997)"
      assert crs.prime_meridian.name == "undefined"
      assert crs.prime_meridian.longitude == 1
  
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 38 for calling a global function with example usage: test_build_custom_datum() without return types