code: def validate_columns(self) -> bool:
      return self._validate_columns
  
imports: from collections import namedtuple
  import numpy
  import pandas
  from ....None import opcodes
  from ....serialization.serializables import BoolField, Float64Field
  from ..aggregation import BaseDataFrameExpandingAgg
label_desc: Use image node_id 5 for calling the DataFrameEwmAgg obj's underlying member method code with example usage: obj.validate_columns() and returns: self