https://www.graalvm.org/ 
public abstract class com.oracle.graal.python.nodes.HiddenAttributes
  minor version: 0
  major version: 59
  flags: flags: (0x0421) ACC_PUBLIC, ACC_SUPER, ACC_ABSTRACT
  this_class: com.oracle.graal.python.nodes.HiddenAttributes
  super_class: java.lang.Object
{
  public static final com.oracle.truffle.api.object.HiddenKey ID_KEY;
    descriptor: Lcom/oracle/truffle/api/object/HiddenKey;
    flags: (0x0019) ACC_PUBLIC, ACC_STATIC, ACC_FINAL

  public static final com.oracle.truffle.api.object.HiddenKey DICT;
    descriptor: Lcom/oracle/truffle/api/object/HiddenKey;
    flags: (0x0019) ACC_PUBLIC, ACC_STATIC, ACC_FINAL

  public static final com.oracle.truffle.api.object.HiddenKey CLASS;
    descriptor: Lcom/oracle/truffle/api/object/HiddenKey;
    flags: (0x0019) ACC_PUBLIC, ACC_STATIC, ACC_FINAL

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=3, locals=0, args_size=0
         0: .line 46
            new com.oracle.truffle.api.object.HiddenKey
            dup
            ldc "object_id"
            invokespecial com.oracle.truffle.api.object.HiddenKey.<init>:(Ljava/lang/String;)V
            putstatic com.oracle.graal.python.nodes.HiddenAttributes.ID_KEY:Lcom/oracle/truffle/api/object/HiddenKey;
         1: .line 47
            new com.oracle.truffle.api.object.HiddenKey
            dup
            ldc "ob_dict"
            invokespecial com.oracle.truffle.api.object.HiddenKey.<init>:(Ljava/lang/String;)V
            putstatic com.oracle.graal.python.nodes.HiddenAttributes.DICT:Lcom/oracle/truffle/api/object/HiddenKey;
         2: .line 48
            new com.oracle.truffle.api.object.HiddenKey
            dup
            ldc "ob_type"
            invokespecial com.oracle.truffle.api.object.HiddenKey.<init>:(Ljava/lang/String;)V
            putstatic com.oracle.graal.python.nodes.HiddenAttributes.CLASS:Lcom/oracle/truffle/api/object/HiddenKey;
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.graal.python.nodes.HiddenAttributes this
         0: .line 45
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // com.oracle.graal.python.nodes.HiddenAttributes this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/graal/python/nodes/HiddenAttributes;
}
SourceFile: "HiddenAttributes.java"