code: def setUp(self):
      self.dtype = numpy.dtype(self.dtype)
      if self.dtype.char in "fF":
          self.r_dtype = numpy.float32
      else:
          self.r_dtype = numpy.float64
      n = self.n
      bs = 1 if self.bs is None else self.bs
      nrhs = 1 if self.nrhs is None else self.nrhs
      a = self._make_well_conditioned_matrices((bs, n, n))
      x = self._make_random_matrices((bs, n, nrhs), cupy)
      b = cupy.matmul(a, x)
      a_shape = (n, n) if self.bs is None else (bs, n, n)
      b_shape = [n]
      if self.bs is not None:
          b_shape.insert(0, bs)
      if self.nrhs is not None:
          b_shape.append(nrhs)
      self.a = a.reshape(a_shape)
      self.b = b.reshape(b_shape)
      self.x_ref = x.reshape(b_shape)
      if self.r_dtype == numpy.float32:
          self.tol = self._tol["f"]
      elif self.r_dtype == numpy.float64:
          self.tol = self._tol["d"]
  
imports: import numpy
  import pytest
  import cupy
  from cupy import cublas
  from cupy import testing
label_desc: Use image node_id 3 for calling the TestBatchedGesv obj's underlying member method code with example usage: obj.setUp() without return types