```ruby
module PartialKs
  class FilteredTable
    attr_reader :table, :parent_model, :custom_filter_relation
    delegate :table_name, :to => :table

    def initialize(table, parent_model, custom_filter_relation: nil)
      @table = table
      @parent_model = parent_model
      @custom_filter_relation = custom_filter_relation
    end

    def kitchen_sync_filter
      if custom_filter_relation
        {"only" => filter_based_on_custom_filter_relation}
      elsif parent_model
        {"only" => filter_based_on_parent_model}
      else
        nil
      end
    end

    protected
    def filter_based_on_parent_model
      table.relation_for_associated_model(parent_model).where_sql.to_s.sub(where_regexp, "")
    end

    def filter_based_on_custom_filter_relation
      if custom_filter_relation.is_a?(ActiveRecord::Relation) || custom_filter_relation.respond_to?(:where_sql)
        only_filter = custom_filter_relation.where_sql.to_s.sub(where_regexp, "")
      elsif custom_filter_relation.is_a?(String)
        only_filter = custom_filter_relation.sub(where_regexp, "")
      end
    end

    def where_regexp
      /\A.*WHERE\s*/i
    end
  end
end
```

Refactor : remove useless variable assignment
user
```ruby
module PartialKs
  class FilteredTable
    attr_reader :table, :parent_model, :custom_filter_relation
    delegate :table_name, :to => :table

    def initialize(table, parent_model, custom_filter_relation: nil)
      @table = table
      @parent_model = parent_model
      @custom_filter_relation = custom_filter_relation
    end

    def kitchen_sync_filter
      if custom_filter_relation
        {"only" => filter_based_on_custom_filter_relation}
      elsif parent_model
        {"only" => filter_based_on_parent_model}
      else
        nil
      end
    end

    protected
    def filter_based_on_parent_model
      table.relation_for_associated_model(parent_model).where_sql.to_s.sub(where_regexp, "")
    end

    def filter_based_on_custom_filter_relation
      if custom_filter_relation.is_a?(ActiveRecord::Relation) || custom_filter_relation.respond_to?(:where_sql)
        custom_filter_relation.where_sql.to_s.sub(where_regexp, "")
      elsif custom_filter_relation.is_a?(String)
        custom_filter_relation.sub(where_regexp, "")
      end
    end

    def where_regexp
      /\A.*WHERE\s*/i
    end
  end
end
```
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