code: def data(self):
      A = sparse.csr_matrix(
          cupy.asarray([[1, 2], [3, 4]], self.dtype)
      ).tocoo()
      B = sparse.csr_matrix(
          cupy.asarray([[5], [6]], self.dtype)
      ).tocoo()
      C = sparse.csr_matrix(cupy.asarray([[7]], self.dtype)).tocoo()
      D = sparse.coo_matrix((0, 0), dtype=self.dtype)
  
      return A, B, C, D
  
imports: import functools
  import re
  from unittest import mock
  import numpy
  import pytest
  import cupy
  from cupy import testing
  from cupy.cuda import runtime
  from cupyx.scipy import sparse
  from cupyx.scipy.sparse import _construct
label_desc: Use image node_id 1 for calling the TestBmat obj's underlying member method code with example usage: obj.data() and returns: A,  B,  C,  D