code: def test_blockpartition_non_positive_partitions():
      with pytest.raises(ValueError):
          blockpartition.solve([42], partitions=0)
      with pytest.raises(ValueError):
          blockpartition.solve([42], partitions=-1)
  
imports: import time
  import pytest
  import torch
  from torch import nn
  from torch.distributed.pipeline.sync._balance import balance_by_size, balance_by_time, blockpartition
  from torch.distributed.pipeline.sync._balance.profile import layerwise_sandbox
  from torch.testing._internal.common_utils import run_tests
label_desc: Use image node_id 3 for calling a global function with example usage: test_blockpartition_non_positive_partitions() without return types