code: def _zip(self, acc: BlockAccessor) -> "pandas.DataFrame":
      r = self.to_pandas().copy(deep=False)
      s = acc.to_pandas()
      for col_name in s.columns:
          col = s[col_name]
          column_names = list(r.columns)
          # Ensure the column names are unique after zip.
          if col_name in column_names:
              i = 1
              new_name = col_name
              while new_name in column_names:
                  new_name = "{}_{}".format(col_name, i)
                  i += 1
              col_name = new_name
          r[col_name] = col
      return r
  
imports: import collections
  import heapq
  from typing import TYPE_CHECKING, Any, Callable, Dict, Iterator, List, Optional, Tuple, TypeVar, Union
  import numpy
  from ray.air.constants import TENSOR_COLUMN_NAME
  from ray.data._internal.table_block import TableBlockAccessor, TableBlockBuilder
  from ray.data._internal.util import find_partitions
  from ray.data.block import Block, BlockAccessor, BlockExecStats, BlockMetadata, KeyType, U
  from ray.data.context import DataContext
  from ray.data.row import TableRow
label_desc: Use image node_id 15 for calling the PandasBlockAccessor obj's underlying member method code with example usage: obj._zip(acc) and returns: r