class_docstr: Grouped rolling window calculation.
  
  See Also
  --------
  cudf.core.window.Rolling
class_docstr_tok: ["Grouped","rolling","window","calculation",".","See","Also","--","--","--","--","cudf.core.window.Rolling"]
code: def _window_to_window_sizes(self, window):
      if is_integer(window):
          return cudautils.grouped_window_sizes_from_offset(
              as_column(range(len(self.obj))).data_array_view(
                  mode="read"
              ),
              self._group_starts,
              window,
          )
      else:
          return cudautils.grouped_window_sizes_from_offset(
              self.obj.index._values.data_array_view(mode="read"),
              self._group_starts,
              window,
          )
  
imports: import itertools
  import numba
  import pandas
  from pandas.api.indexers import BaseIndexer
  import cudf
  from cudf import _lib
  from cudf.api.types import is_integer, is_number
  from cudf.core import column
  from cudf.core._compat import PANDAS_GE_150
  from cudf.core.buffer import acquire_spill_lock
  from cudf.core.column.column import as_column
  from cudf.core.mixins import Reducible
  from cudf.utils import cudautils
  from cudf.utils.utils import GetAttrGetItemMixin
label_desc: Use image node_id 2 for calling the RollingGroupby obj's underlying member method code with example usage: obj._window_to_window_sizes(window) and returns: cudautils, cudautils