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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def tar_gzip_dir(directory, destination, base=None):
 """Creates a tar.gz from a directory."""

    dest_file = tarfile.open(destination, 'w:gz')
    abs_dir_path = os.path.abspath(directory)
    base_name = abs_dir_path + "/"
    base = base or os.path.basename(directory)
    for path, dirnames, filenames in os.walk(abs_dir_path):
        rel_path = path[len(base_name):]
        dir_norm_path = os.path.join(base, rel_path)
        dir_tar_info = dest_file.gettarinfo(name=path)
        dir_tar_info.name = dir_norm_path
        dest_file.addfile(dir_tar_info)
        for filename in filenames:
            actual_path = os.path.join(path, filename)
            norm_path = os.path.join(base, rel_path, filename)
            tar_info = dest_file.gettarinfo(name=actual_path)
            tar_info.name = norm_path
            new_file = open(actual_path, 'rb')
            dest_file.addfile(tar_info, new_file)
    dest_file.close()