code: def to_double(g):
      r"""Cast this graph to use float64 (double-precision) for any
      floating-point edge and node feature data.
  
      A shallow copy is returned so that the original graph is not modified.
      Feature tensors that are not floating-point will not be modified.
  
      Returns
      -------
      DGLGraph
          Clone of graph with the feature data converted to float64.
      """
      ret = copy.copy(g)
      ret._edge_frames = [frame.double() for frame in ret._edge_frames]
      ret._node_frames = [frame.double() for frame in ret._node_frames]
      return ret
  
imports: import copy
  from collections.abc import Iterable, Mapping
  import numpy
  import scipy.sparse
  import scipy.sparse.linalg
  from ..utils import version
  from ..None import backend, batch, convert, function, ndarray, subgraph, utils
  from .._ffi.function import _init_api
  from ..base import dgl_warning, DGLError, EID, NID
  from ..frame import Frame
  from ..heterograph import DGLGraph
  from ..heterograph_index import create_heterograph_from_relations, create_metagraph_index
  from ..partition import metis_partition, metis_partition_assignment, partition_graph_with_halo
  from ..sampling.neighbor import sample_neighbors
label_desc: Use image node_id 42 for calling a global function with example usage: to_double(g) and returns: ret