diff --git a/httpie/status.py b/httpie/status.py
index 28c75b63..2abf2918 100644
--- a/httpie/status.py
+++ b/httpie/status.py
@@ -1,23 +1,24 @@
-from enum import IntEnum
+from enum import IntEnum, unique
 
 
+@unique
 class ExitStatus(IntEnum):
-    """Program exit code constants."""
+    """Program exit status code constants."""
     SUCCESS = 0
     ERROR = 1
-    PLUGIN_ERROR = 7
-
-    # 128+2 SIGINT <http://www.tldp.org/LDP/abs/html/exitcodes.html>
-    ERROR_CTRL_C = 130
-
     ERROR_TIMEOUT = 2
-    ERROR_TOO_MANY_REDIRECTS = 6
 
-    # Used only when requested with --check-status:
+    # See --check-status
     ERROR_HTTP_3XX = 3
     ERROR_HTTP_4XX = 4
     ERROR_HTTP_5XX = 5
 
+    ERROR_TOO_MANY_REDIRECTS = 6
+    PLUGIN_ERROR = 7
+    # 128+2 SIGINT
+    # <http://www.tldp.org/LDP/abs/html/exitcodes.html>
+    ERROR_CTRL_C = 130
+
 
 def http_status_to_exit_status(http_status: int, follow=False) -> ExitStatus:
     """