code: def dtype_values(self):
      return self._dtype_values
  
imports: import numpy
  import pandas
  from pandas.api.types import CategoricalDtype
  from ...None import opcodes
  from ...core import recursive_tile
  from ...serialization.serializables import AnyField, StringField, ListField
  from ...tensor.base import sort
  from ...utils import pd_release_version
  from ..core import DATAFRAME_TYPE, SERIES_TYPE
  from ..operands import DataFrameOperand, DataFrameOperandMixin
  from ..utils import build_empty_df, build_empty_series, parse_index
label_desc: Use image node_id 2 for calling the DataFrameAstype obj's underlying member method code with example usage: obj.dtype_values() and returns: self