code: def _calc_out_dtypes(self, in_groupby):
      mock_groupby = in_groupby.op.build_mock_groupby()
      func_name = getattr(self, "_func_name")
  
      if func_name == "fillna":
          result_df = mock_groupby.fillna(
              value=self.value,
              method=self.method,
              axis=self.axis,
              limit=self.limit,
              downcast=self.downcast,
          )
      else:
          result_df = getattr(mock_groupby, func_name)(limit=self.limit)
  
      if isinstance(result_df, pd.DataFrame):
          self.output_types = [OutputType.dataframe]
          return result_df.dtypes
      else:
          self.output_types = [OutputType.series]
          return result_df.name, result_df.dtype
  
imports: import numpy
  import pandas
  from ...None import opcodes
  from ...core import OutputType
  from ...serialization.serializables import AnyField, DictField, StringField, Int64Field
  from ..utils import parse_index, build_empty_df, build_empty_series
  from ..operands import DataFrameOperandMixin, DataFrameOperand
label_desc: Use image node_id 1 for calling the GroupByFillOperand obj's underlying member method code with example usage: obj._calc_out_dtypes(in_groupby) and returns: result_df, result_df,  result_df