code: def setup(self, n, solver):
      if solver == "dense" and n >= 25:
          raise NotImplementedError()
  
      self.b = np.ones(n * n)
      self.P_sparse = _create_sparse_poisson2d(n)
  
      if solver == "dense":
          self.P_dense = self.P_sparse.A
  
file_path: scipy/benchmarks/benchmarks/sparse_linalg_solve.py
imports: import numpy
  from numpy.testing import assert_equal
  from .common import Benchmark, safe_import
label_desc: Use image node_id 1 for calling the Bench obj's underlying member method code with example usage: obj.setup(n, solver) without return types