code: def var_aggregate(x2, x, n, ddof):
      try:
          with warnings.catch_warnings(record=True):
              warnings.simplefilter("always")
              result = (x2 / n) - (x / n) ** 2
          if ddof != 0:
              result = result * n / (n - ddof)
          return result
      except ZeroDivisionError:
          return np.float64(np.nan)
  
imports: import math
  import textwrap
  import warnings
  import numpy
  import pandas
  from tlz import partition_all
  from dask import dataframe
  from dask.base import normalize_token, tokenize
  from dask.dataframe.core import Scalar, handle_out, make_meta, map_partitions
  from dask.dataframe.utils import raise_on_meta_error
  from dask.highlevelgraph import HighLevelGraph
  from dask.utils import M, OperatorMethodMixin, apply, derived_from, funcname
  import cudf
  from cudf import _lib
  from cudf.utils.nvtx_annotation import _dask_cudf_nvtx_annotate
  from dask_cudf import sorting
  from dask_cudf.accessors import ListMethods, StructMethods
  from dask_cudf.sorting import _deprecate_shuffle_kwarg, _get_shuffle_method
label_desc: Use image node_id 2 for calling a global function with example usage: var_aggregate(x2, x, n, ddof) and returns: result, np