code: def _rmatvec(self, x):
      assert_equal(max(x.shape), np.size(x))
      return self.A.T.conjugate().dot(x)
  
imports: import os
  import re
  import copy
  import numpy
  from numpy.testing import assert_allclose, assert_equal, assert_array_equal
  import pytest
  from scipy.linalg import svd, null_space
  from scipy.sparse import csc_matrix, issparse, spdiags, random
  from scipy.sparse.linalg import LinearOperator, aslinearoperator
  from scipy.sparse.linalg import svds
  from scipy.sparse.linalg._eigen.arpack import ArpackNoConvergence
label_desc: Use image node_id 3 for calling the CheckingLinearOperator obj's underlying member method code with example usage: obj._rmatvec(x) and returns: self