if (extensions != null) {
                for (Extension ext : extensions) {
                    String version;
                    if (ext.getVersion() == null || ext.getVersion().isEmpty()) {
                        version = "RELEASE";
                    } else {
                        version = ext.getVersion();
                    }

        assertEquals(1, ((List<?>) pom.getValue("build/extensions")).size());
        assertEquals("org.apache.maven.its.ext", pom.getValue("build/extensions[1]/groupId"));
        assertEquals("ext", pom.getValue("build/extensions[1]/artifactId"));
        assertEquals("3.0", pom.getValue("build/extensions[1]/version"));

			userDefined["etag"] = opts.PreserveETag
		}
	}

	// Guess content-type from the extension if possible.
	if userDefined["content-type"] == "" {
		userDefined["content-type"] = mimedb.TypeByExtension(path.Ext(object))
	}

	// if storageClass is standard no need to save it as part of metadata.
	if userDefined[xhttp.AmzStorageClass] == storageclass.STANDARD {
		delete(userDefined, xhttp.AmzStorageClass)
	}