def METHOD_NAME(in_folder=TMP_FOLDER):
    """
    Generate spm module in the specified folder, default
    to the system's tmp folder.
    After generation, user can simply use the prompt SPM
    code to include the ANTLR4 Swift runtime package.
    :param in_folder: the folder where we generate the SPM module.
    :return: None
    """
    tmp_antlr_folder = in_folder + "Antlr4-tmp-" + str(int(time.time()))
    os.mkdir(tmp_antlr_folder)
    # Copy folders and SPM manifest file.
    dirs_to_copy = ["Sources", "Tests"]
    for dir_to_copy in dirs_to_copy:
        shutil.copytree(DIR + "/" + dir_to_copy, tmp_antlr_folder + "/" + dir_to_copy)
    shutil.copy("Package.swift", tmp_antlr_folder)
    os.chdir(tmp_antlr_folder)
    check_call(["git", "init"])
    check_call(["git", "add", "*"])
    check_call(["git", "commit", "-m", "Initial commit."])
    check_call(["git", "tag", "{}.0.0".format(MAJOR_VERSION)])
    antlr_says("Created local repository.")
    antlr_says("(swift-tools-version:3.0) " 
               "Put .Package(url: \"{}\", majorVersion: {}) in Package.swift.".format(os.getcwd(), MAJOR_VERSION))
    antlr_says("(swift-tools-wersion:4.0) "
               "Put .package(url: \"{}\", from: \"{}.0.0\") in Package.swift "
               "and add \"Antlr4\" to target dependencies. ".format(os.getcwd(), MAJOR_VERSION))