code: def uniform(obj):
      """
      Finds all common dimension keys in the object including subsets of
      dimensions. If there are is no common subset of dimensions, None
      is returned.
      """
      from .spaces import HoloMap
  
      dim_groups = obj.traverse(lambda x: tuple(x.kdims), (HoloMap,))
      if dim_groups:
          dgroups = [frozenset(d.name for d in dg) for dg in dim_groups]
          return all(
              g1 <= g2 or g1 >= g2 for g1 in dgroups for g2 in dgroups
          )
      return True
  
file_path: holoviews/holoviews/core/traversal.py
imports: from collections import defaultdict
  from operator import itemgetter
  from .dimension import Dimension
  from .util import merge_dimensions
label_desc: Use image node_id 2 for calling a global function with example usage: uniform(obj) and returns: True, all