         let filePrefix = namer.typePrefix(forFile: fileDescriptor)
         p.print(
           "\n",
+          "// MARK: - File's ExtensionMap: \(filePrefix)\(filenameAsIdentifer)_Extensions\n",
+          "\n",
           "/// A `SwiftProtobuf.SimpleExtensionMap` that includes all of the extensions defined by\n",
           "/// this .proto file. It can be used any place an `SwiftProtobuf.ExtensionMap` is needed\n",
           "/// in parsing, or it can be combined with other `SwiftProtobuf.SimpleExtensionMap`s to create\n",


    func generateProtobufExtensionDeclarations(printer p: inout CodePrinter) {
      guard !extensions.isEmpty else { return }

      func endScope() {
          p.outdent()

    func generateMessageSwiftExtensions(printer p: inout CodePrinter) {
        guard !extensions.isEmpty else { return }

        p.print(
            "\n",
            "// MARK: - Extension Properties\n",
            "\n",
            "// Swift Extensions on the exteneded Messages to add easy access to the declared\n",
            "// extension fields. The names are based on the extension field name from the proto\n",
            "// declaration. To avoid naming collisions, the names are prefixed with the name of\n",
            "// the scope where the extend directive occurs.\n")

        // Reorder the list so they are grouped by the Message being extended, but
        // maintaining the order they were within the file within those groups.
        let grouped: [ExtensionGenerator] = extensions.enumerated().sorted {
