{* ../../docs_src/header_params/tutorial002_an_py310.py hl[10] *}

/// warning

Before setting `convert_underscores` to `False`, bear in mind that some HTTP proxies and servers disallow the usage of headers with underscores.

///

## Duplicate headers { #duplicate-headers }

It is possible to receive duplicate headers. That means, the same header with multiple values.

// checkKMSActionAllowed checks for authorization for a specific action on a resource.
func checkKMSActionAllowed(r *http.Request, owner bool, cred auth.Credentials, action policy.KMSAction, resource string) bool {
	return globalIAMSys.IsAllowed(policy.Args{
		AccountName:     cred.AccessKey,
		Groups:          cred.Groups,
		Action:          policy.Action(action),
		ConditionValues: getConditionValues(r, "", cred),
		IsOwner:         owner,

A default retention period and retention mode can be configured on a bucket to be applied to objects created in that bucket. Independent of retention, an object can also be under legal hold. This effectively disallows all deletes of an object under legal hold until the legal hold is removed by an API call.

## Get Started

### 1. Prerequisites

        // Check protocol versions
        assertNotNull(testConfig.getMinimumVersion());
        assertNotNull(testConfig.getMaximumVersion());

        // Check disallow compound
        assertNotNull(testConfig.disallowCompound);
        assertTrue(testConfig.disallowCompound.contains("Smb2SessionSetupRequest"));
        assertTrue(testConfig.disallowCompound.contains("Smb2TreeConnectRequest"));

&:not(:last-child) {\n          @include border-right-radius(0);\n\n          .card-img-top,\n          .card-header {\n            // stylelint-disable-next-line property-disallowed-list\n            border-top-right-radius: 0;\n          }\n          .card-img-bottom,\n          .card-footer {\n            // stylelint-disable-next-line property-disallowed-list\n            border-bottom-right-radius: 0;\n          }\n        }\n\n        &:not(:first-child) {\n          @include border-left-radius(0);\n\n   ...

		if r.Destination.LegacyArn() {
			legacyArn = true
		}
		if c.RoleArn == "" && !r.Destination.TargetArn() {
			return errDestinationArnMissing
		}
	}
	// disallow combining old replication configuration which used RoleArn as target ARN with multiple
	// destination replication
	if c.RoleArn != "" && len(targetMap) > 1 {
		return errRoleArnPresentForMultipleTargets
	}

 public:
  AbstractOperationKind getKind() const { return kind_; }

  // Release any underlying resources, including the interface object.
  //
  // WARNING: The destructor of this class is marked as protected to disallow
  // clients from directly destroying this object since it may manage it's own
  // lifetime through ref counting. Thus this must be allocated on the heap and

        this.redirectHttpStatusPattern = redirectHttpStatusPattern;
    }

    /**
     * Sets whether to use robots.txt disallow rules.
     *
     * @param useRobotsTxtDisallows True to use disallow rules, false otherwise
     */
    public void setUseRobotsTxtDisallows(final boolean useRobotsTxtDisallows) {
        this.useRobotsTxtDisallows = useRobotsTxtDisallows;
    }

		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
		return
	}

	var ignoreInUse bool
	if forceStr := r.Form.Get("force"); forceStr != "" {
		ignoreInUse, _ = strconv.ParseBool(forceStr)
	}

	// Disallow remote tiers with internal storage class names
	switch cfg.Name {
	case storageclass.STANDARD, storageclass.RRS:
		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, errTierReservedName), r.URL)
		return
	}

            assertTrue(result);
            verify(mockConfig, times(2)).isAllowCompound("TestServerMessageBlock2Request");
        }

        @Test
        @DisplayName("allowChain should return false when config disallows compound")
        void testAllowChainDisallowed() {
            TestServerMessageBlock2Request nextRequest = new TestServerMessageBlock2Request(mockConfig);