code: def _rmatvec(self, x):
      A_T = self._A.T
      x = x.ravel()
      for i in range(self._p):
          x = A_T.dot(x)
      return x
  
imports: import numpy
  import scipy.special
  from scipy._lib._util import float_factorial
  from scipy.linalg.basic import solve, solve_triangular
  from scipy.sparse.base import isspmatrix
  from scipy.sparse.linalg import spsolve
  from scipy.sparse.sputils import is_pydata_spmatrix
  import scipy.sparse
  import scipy.sparse.linalg
  from scipy.sparse.linalg.interface import LinearOperator
  from ._expm_multiply import _ident_like, _exact_1_norm
label_desc: Use image node_id 3 for calling the MatrixPowerOperator obj's underlying member method code with example usage: obj._rmatvec(x) and returns: x