%subscribers = {
	"user_001" = {
		"name" => "sam",
		"age" => "13",
		"color" =>['red','blue']
		"item"=>{
			"old" =>['PC','pen'],
			"new" =>['tap','car']
		},
	"user_002" = {
		"name" => "ali",
		"age" => "54",
		"color" =>['red','null','green']
		"item"=>{
			"old" =>['phone','TV']
		},
	"user_003" = {
		"name" => "foo",
		"age" => "02",
		"item"=>{
			"old" =>['']
		},
		....
	}
}

#[our data are more nasty and complex]