code: def test_indices(self) -> None:
      tb1_config = EmbeddingConfig(
          name="t1",
          embedding_dim=5,
          num_embeddings=10,
          feature_names=["f1", "f2"],
      )
      tb2_config = EmbeddingConfig(
          name="t2",
          embedding_dim=5,
          num_embeddings=10,
          feature_names=["f2"],
      )
      ec = EmbeddingCollection(
          tables=[tb1_config, tb2_config],
          need_indices=True,
      )
  
      id_list_features = KeyedJaggedTensor.from_offsets_sync(
          keys=["f1", "f2"],
          values=torch.tensor([0, 1, 2, 3]),
          offsets=torch.tensor([0, 2, 3, 3, 4]),
      )
  
      sequence_embeddings = ec(
          features=id_list_features,
      )
      self.assertTrue(
          torch.equal(
              sequence_embeddings["f1"].weights(),
              torch.tensor([0, 1, 2]),
          )
      )
      self.assertTrue(
          torch.equal(
              sequence_embeddings["f2@t1"].weights(), torch.tensor([3])
          )
      )
      self.assertTrue(
          torch.equal(
              sequence_embeddings["f2@t2"].weights(), torch.tensor([3])
          )
      )
  
imports: import unittest
  from functools import partial
  import torch
  import torch.fx
  from torchrec.fx import symbolic_trace
  from torchrec.modules.embedding_configs import EmbeddingBagConfig, EmbeddingConfig
  from torchrec.modules.embedding_modules import EmbeddingBagCollection, EmbeddingCollection
  from torchrec.sparse.jagged_tensor import KeyedJaggedTensor
label_desc: Use image node_id 2 for calling the EmbeddingCollectionTest obj's underlying member method code with example usage: obj.test_indices() without return types