code: def embd_transform_error(self, embedding, covmats, n_components):
      embd = embedding(n_components=n_components)
      embd = embd.fit(covmats)
      with pytest.raises(AssertionError):
          embd.transform(covmats[:-1, :-1, :-1])
  
imports: from conftest import get_metrics
  import numpy
  from sklearn.neighbors import NearestCentroid
  from pyriemann.datasets import make_gaussian_blobs
  from pyriemann.embedding import SpectralEmbedding, LocallyLinearEmbedding, barycenter_weights, locally_linear_embedding
  import pytest
label_desc: Use image node_id 4 for calling the TestEmbedding obj's underlying member method code with example usage: obj.embd_transform_error(embedding, covmats, n_components) without return types