class_docstr: MXNet internal sampler implemented in c++.
  
  Parameters
  ----------
  name : str
      Name of the sampler.
class_docstr_tok: ["MXNet","internal","sampler","implemented","in","c++",".","Parameters","--","--","--","--","--","name",":","str","Name","of","the","sampler","."]
code: def __len__(self):
      try:
          size = len(self._iter)
      except TypeError:
          raise TypeError(
              "Iterator {} does not provide length info".format(
                  self._iter
              )
          )
      return size
  
imports: import sys
  import ctypes
  from .dataset import Dataset
  from .sampler import Sampler
  from ...base import _LIB
  from ...base import c_str_array, mx_uint, py_str
  from ...base import DatasetHandle, NDArrayHandle, BatchifyFunctionhandle
  from ...base import check_call, build_param_doc
  from ...ndarray import NDArray
  from ...ndarray import _ndarray_cls
  from ...numpy.multiarray import _np_ndarray_cls
  from ...util import is_np_array, default_array
  from ...io import io
label_desc: Use image node_id 2 for calling the MXSampler obj's underlying member method code with example usage: obj.__len__() and returns: size