def read
      @store.transaction(true) do
        @store.roots.each_with_object({}) do |key, obj|
          obj[key] = @store[key]
        end
      end
    end
def read
      @store.transaction(true) do
        @store.roots.each_with_object({}) do |key, obj|
          obj[key] = @store[key]
        end
      end
    end
returns copy of data stored