class_docstr: Represents data from mars tensor
code: def _process_index(
      self,
      index: Union[TileableType, pd.Index],
      inputs: List[EntityType],
  ):
      if not isinstance(index, pd.Index):
          if isinstance(index, INDEX_TYPE):
              index_value = index.index_value
              inputs.append(index)
          elif isinstance(index, ENTITY_TYPE):
              index = astensor(index)
              if index.ndim != 1:
                  raise ValueError(
                      f"index should be 1-d, got {index.ndim}-d"
                  )
              index_value = parse_index(
                  pd.Index([], dtype=index.dtype),
                  index,
                  type(self).__name__,
              )
              inputs.append(index)
          else:
              index = pd.Index(index)
              index_value = parse_index(index)
      else:
          index_value = parse_index(index)
      return index_value
  
imports: from collections import OrderedDict
  from typing import Any, Dict, List, Union
  import numpy
  import pandas
  from ...None import opcodes
  from ...core import ENTITY_TYPE, OutputType, recursive_tile
  from ...core.context import Context
  from ...serialization.serializables import KeyField, AnyField
  from ...tensor.core import Tensor
  from ...tensor.datasource import tensor
  from ...tensor.utils import unify_chunks
  from ...typing import EntityType, TileableType
  from ...utils import has_unknown_shape
  from ..core import INDEX_TYPE, SERIES_TYPE
  from ..operands import DataFrameOperand, DataFrameOperandMixin
  from ..utils import parse_index
label_desc: Use image node_id 4 for calling the DataFrameFromTensor obj's underlying member method code with example usage: obj._process_index(index, inputs) and returns: index_value