code: def nrows(self):
      return self._nrows
  
imports: from h2o.utils.compatibility import *
  from collections import OrderedDict
  import copy
  import gc
  import inspect
  import math
  import time
  import numbers
  import tabulate
  import h2o
  from h2o.backend.connection import H2OConnectionError
  from h2o.utils.shared_utils import _is_fr, _py_tmp_key
  from h2o.model.model_base import ModelBase
  from h2o.expr_optimizer import optimize
label_desc: Use image node_id 2 for calling the H2OCache obj's underlying member method code with example usage: obj.nrows() and returns: self