#!/usr/bin/env python3

import os

PREFIX = "some prefix"

for root, dirs, files in os.walk("."):
    dir_fd = os.open(root, os.O_DIRECTORY)
    for f in files:
        link_path = os.path.join(root, f)
        if os.path.islink(link_path):
            real_path = os.path.realpath(link_path)
            new_real_path = real_path[len(PREFIX):]
            print(new_real_path, "|", f, "|", root)
            os.unlink(link_path)
            os.symlink(new_real_path, f, dir_fd=dir_fd)