code: def compute_var(dist):
      icvr = [vr.get() for vr in dist.values()]
      n = len(icvr)
      return sum(icvr) / n if n > 0 else 0.0
  
imports: from __future__ import annotations
  from .variance_reduction_split_criterion import VarianceReductionSplitCriterion
label_desc: Use image node_id 3 for calling the IntraClusterVarianceReductionSplitCriterion obj's underlying member method code with example usage: obj.compute_var(dist) and returns: unknown