code: def _rmatvec(self, x):
      assert_equal(max(x.shape), np.size(x))
      return self.A.T.conjugate().dot(x)
  
imports: from __future__ import division, print_function, absolute_import
  import threading
  import itertools
  import numpy
  from numpy.testing import assert_allclose, assert_array_almost_equal_nulp, assert_equal, assert_array_equal
  from pytest import raises
  import pytest
  from numpy import dot, conj, random
  from scipy.linalg import eig, eigh, hilbert, svd
  from scipy.sparse import csc_matrix, csr_matrix, isspmatrix, diags, rand
  from scipy.sparse.linalg import LinearOperator, aslinearoperator
  from scipy.sparse.linalg.eigen.arpack import eigs, eigsh, svds, ArpackNoConvergence, arpack
  from scipy._lib._gcutils import assert_deallocated, IS_PYPY
  from scipy._lib._numpy_compat import suppress_warnings
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