import jinja2

template_file = r"@INDEX_TEMPLATE_FILE@"
output_file = r"@INDEX_FILE@"

substitutions = {
    "HEADLINE": "@CURRENT_FOLDER_NAME@",
}

with open(template_file, 'r') as f:
    template = jinja2.Template(f.read())

with open(output_file, 'w') as f:
    f.write(template.render(**substitutions))