code: def var(self):
      return self.aggregate("var")
  
imports: from collections import OrderedDict
  from ....serialization.serializables import BoolField, Int32Field, Int64Field, StringField
  from ....utils import pd_release_version
  from ...utils import validate_axis
  from ..core import Window
label_desc: Use image node_id 14 for calling the Expanding obj's underlying member method code with example usage: obj.var() and returns: self