def to_h
      hash = {}
      @data.each_pair do |key, value|
        hash[key] = value.to_h
      end
      
      hash      
    end
def to_h
      hash = {}
      @data.each_pair do |key, value|
        hash[key] = value.to_h
      end
      
      hash      
    end
Returns all city/state data as a pure Ruby hash (e.g. no Structs as values)