如何用python从这个字典中提取值?

我有一本这样的字典:

{"message":"{\"_\":\"user\",\"pFlags\":{\"contact\":true},\"flags\":2175,\"id\":379951860,\"access_hash\":\"6967195540985199805\",\"first_name\":\"پژوا\",\"last_name\":\"روزبهی\",\"username\":\"mramtd2\",\"phone\":\"989157145632\",\"photo\":{\"_\":\"userProfilePhoto\",\"photo_id\":\"1631880813210609625\",\"photo_small\":{\"_\":\"fileLocation\",\"dc_id\":4,\"volume_id\":\"448413446\",\"local_id\":476387,\"secret\":\"655623158723369503\"},\"photo_big\":{\"_\":\"fileLocation\",\"dc_id\":4,\"volume_id\":\"448413446\",\"local_id\":476389,\"secret\":\"13993366131879811943\"}},\"status\":{\"_\":\"userStatusOffline\",\"was_online\":1558046876}}","phone":"989157145632","@version":"1","typ":"telegram_contacts","access_hash":"6967195540985199805","id":379951860,"@timestamp":"2020-01-26T13:50:12.793Z","path":"/home/user/mirror_01/users_5d65f610ec18aa615a5f580c.log","username":"mramtd2","type":"redis","flags":2175,"host":"ubuntu","imported_from":"telegram_contacts"}

如何提取 first_name , last_name , id 和 phone 这本字典里的值?