code: def test_diffeomorphism(self, base_point, expected, atol):
      res = self.diffeo.diffeomorphism(base_point)
      self.assertAllClose(res, expected, atol=atol)
  
imports: import pytest
  import geomstats.backend
  from geomstats.geometry.diffeo import AutodiffDiffeo
  from geomstats.test.random import RandomDataGenerator
  from geomstats.test.test_case import TestCase
  from geomstats.test.vectorization import generate_vectorization_data
label_desc: Use image node_id 2 for calling the DiffeoTestCase obj's underlying member method code with example usage: obj.test_diffeomorphism(base_point, expected, atol) without return types