code: def _execute_dataframe_map(cls, ctx, op):
      a, pivots = [ctx[c.key] for c in op.inputs]
      out = op.outputs[0]
  
      if len(a) == 0:
          # when the chunk is empty, no slices can be produced
          for i in range(op.n_partition):
              ctx[out.key, (i,)] = a
          return
  
      # use numpy.searchsorted to find split positions.
      by = op.by
  
      distinct_col = (
          _PSRS_DISTINCT_COL
          if a.columns.nlevels == 1
          else (_PSRS_DISTINCT_COL,) + ("",) * (a.columns.nlevels - 1)
      )
      if distinct_col in a.columns:
          by = list(by) + [distinct_col]
  
      try:
          poses = cls._calc_poses(a[by], pivots, op.ascending)
      except TypeError:
          poses = cls._calc_poses(
              a[by].fillna(_largest),
              pivots.fillna(_largest),
              op.ascending,
          )
  
      poses = (None,) + tuple(poses) + (None,)
      for i in range(op.n_partition):
          values = a.iloc[poses[i] : poses[i + 1]]
          if is_cudf(values):  # pragma: no cover
              values = values.copy()
          ctx[out.key, (i,)] = values
  
imports: import os
  import numpy
  import pandas
  from ...None import opcodes
  from ...core.operand import OperandStage, MapReduceOperand
  from ...utils import lazy_import, calc_nsplits
  from ...serialization.serializables import AnyField, Int32Field, ListField, StringField, BoolField
  from ...tensor.base.psrs import PSRSOperandMixin
  from ..core import IndexValue, OutputType
  from ..utils import standardize_range_index, parse_index, is_cudf
  from ..operands import DataFrameOperandMixin, DataFrameOperand, DataFrameShuffleProxy
label_desc: Use image node_id 4 for calling the DataFramePSRSShuffle obj's underlying member method code with example usage: obj._execute_dataframe_map(cls, ctx, op) without return types