anchor.diff:  status_code(unexpected_content) -> 400;
   status_code(canned_acl_and_header_grant) -> 400;
   status_code(malformed_acl_error) -> 400;
  -status_code(_) -> 503.
  +status_code(ErrorName) ->
  +    _ = lager:debug("Unknown Error Name: ~p", [ErrorName]),
  +    503.
   
   -spec respond(term(), #wm_reqdata{}, #context{}) ->
                        {binary(), #wm_reqdata{}, #context{}}.
  
positive.code: error_message(invalid_bucket_name) -> "The specified bucket is not valid.";
  error_message(unexpected_content) -> "This request does not support content";
  error_message(canned_acl_and_header_grant) -> "Specifying both Canned ACLs and Header Grants is not allowed";
  error_message(_) -> "Please reduce your request rate.".
  
  error_code(invalid_access_key_id) -> "InvalidAccessKeyId";
  error_code(access_denied) -> "AccessDenied";
  
negative.code: error_code(canned_acl_and_header_grant) -> "InvalidRequest";
  error_code(malformed_acl_error) -> "MalformedACLError";
  error_code(ErrorName) ->
      _ = lager:debug("Unknown Error Name: ~p", [ErrorName]),
      "ServiceUnavailable".
  
  %% These should match:
  