code: def test_fit(self, estimator, X, expected):
      estimate_ = estimator.fit(X, y=None).estimate_
  
      dist = estimator.metric.dist(estimate_, expected)
      self.assertAllClose(dist, 0.0)
  
imports: import geomstats.backend
  from geomstats.learning.aac import AAC
  from geomstats.test.parametrizers import Parametrizer
  from geomstats.test.test_case import TestCase
  from .data.aac import AACFrechetMeanTestData, AACGGPCATestData, AACRegressionTestData, AACTestData
label_desc: Use image node_id 1 for calling the TestAACFrechetMean obj's underlying member method code with example usage: obj.test_fit(estimator, X, expected) without return types