code: def _execute_combine_function(
      cls,
      op: "DataFrameEwmAgg",
      func,
      prev_inputs,
      local_inputs,
      func_cols,
  ):
      exec_cache = cls._exec_cache[op.key]
      pred_exponent = exec_cache.get("pred_exponent")
      if func_cols and pred_exponent is not None:
          pred_exponent = (
              pred_exponent[func_cols]
              if pred_exponent is not None
              else None
          )
      return func(
          prev_inputs,
          local_inputs,
          axis=op.axis,
          alpha=op.alpha,
          alpha_ignore_na=op.alpha_ignore_na,
          pred_exponent=pred_exponent,
      )
  
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 13 for calling the DataFrameEwmAgg obj's underlying member method code with example usage: obj._execute_combine_function(cls, op, func, prev_inputs, local_inputs, func_cols) and returns: func