code: def setup_sakurai_inverse(self, n, solver):
      self.shape = (n, n)
      sakurai_obj = Sakurai(n)
      self.A = sakurai_obj.tobanded().astype(np.float64)
      self.eigenvalues = sakurai_obj.eigenvalues
  
file_path: scipy/benchmarks/benchmarks/sparse_linalg_lobpcg.py
imports: import numpy
  import warnings
  from .common import Benchmark, safe_import
label_desc: Use image node_id 4 for calling the Bench obj's underlying member method code with example usage: obj.setup_sakurai_inverse(n, solver) without return types