code: def execute(cls, ctx, op):
      sizes = [ctx[inp.key] for inp in op.inputs]
      total_bytes = sum(sizes)
      offsets = np.cumsum([0] + sizes)[:-1]
  
      # write NULL bytes into file
      with open_file(
          op.path, mode="wb", storage_options=op.storage_options
      ) as f:
          rest = total_bytes
          while rest > 0:
              # at most 4M
              write_bytes = min(4 * 1024**2, rest)
              f.write(b"\00" * write_bytes)
              rest -= write_bytes
  
      ctx[op.outputs[0].key] = offsets
  
imports: from io import StringIO
  import numpy
  import pandas
  from ...None import opcodes
  from ...core import OutputType, recursive_tile
  from ...core.operand import OperandStage
  from ...lib.filesystem import open_file
  from ...serialization.serializables import KeyField, AnyField, StringField, ListField, BoolField, Int32Field, Int64Field, DictField
  from ...tensor.core import TensorOrder
  from ...tensor.operands import TensorOperand, TensorOperandMixin
  from ..operands import DataFrameOperand, DataFrameOperandMixin
  from ..utils import parse_index
label_desc: Use image node_id 4 for calling the DataFrameToCSVStat obj's underlying member method code with example usage: obj.execute(cls, ctx, op) without return types