use python-markdown to generate Gitlab compatible TOC.

gitlab-toc.py

import markdown

def inc_header():     data = [0]
    def fun(x, *rest):
        header = 'toc_%d' % data[0]
        data[0] += 1
        return header
    return fun


if __name__ == '__main__':
    fd = open('test.md')
    md_text = fd.read()
    toc_html = markdown.markdown(md_text, extensions=['toc'],
        extension_configs={'toc': [('slugify', inc_header())]})