code: def process(object, options={})
        return nil if object.nil? or object.empty?
        object = object.encode('UTF-8', 'binary', invalid: :replace, undef: :replace, replace: '')
        object += " " if object =~ /;$/
        return object if filter.empty? and pivot.empty?
        filtered = object.split(';').values_at(*filter.flatten.uniq)
        pivot_each_column(object.split(';')) do |column, match|
          filtered << column if match
        end
        if !filtered.last.nil? and filtered.last.empty?
          filtered.compact.join(';') + " " 
        else
          filtered.compact.join(';')
        end
      end
docs: Processes the filter and returns the values that respect the filter