code: def test_posv(self):
      if not cusolver.check_availability("potrsBatched"):
          pytest.skip("potrsBatched is not available")
      a = self._create_posdef_matrix(cupy, self.shape, self.dtype)
      n = a.shape[-1]
      identity_matrix = cupy.eye(n, dtype=a.dtype)
      b = cupy.empty(a.shape, a.dtype)
      b[...] = identity_matrix
      with cupyx.errstate(linalg="ignore"):
          with pytest.raises(cupy.cuda.cusolver.CUSOLVERError):
              lapack.posv(a, b)
  
imports: import unittest
  import numpy
  import pytest
  import cupy
  from cupy import testing
  import cupyx
  from cupyx import cusolver, lapack
label_desc: Use image node_id 1 for calling the TestXFailBatchedPosv obj's underlying member method code with example usage: obj.test_posv() without return types