code: def expand(self):
      expanded_variables = super(CategoricalVariable, self).expand()
      for v in expanded_variables:
          v.dimensionality_in_model = len(self.domain)
      return expanded_variables
  
imports: import numpy
  from copy import deepcopy
  from ..errors import InvalidConfigError
label_desc: Use image node_id 2 for calling the CategoricalVariable obj's underlying member method code with example usage: obj.expand() and returns: expanded_variables