# -*- coding: utf-8 -*-

import os
import stat


def rec_rmdir(root, callback, preserve=True):
    for path in (os.path.join(root, p) for p in os.listdir(root)):
        st = os.stat(path)
        if stat.S_ISREG(st.st_mode):
            callback(path)
        elif stat.S_ISDIR(st.st_mode):
            rec_rmdir(path, callback, preserve=False)
    if not preserve:
        try:
            os.rmdir(root)
        except IOError:
            pass


def process_file_and_remove(path):
    # process the file
    # ...
    os.remove(path)


rec_rmdir("/path/to/root", process_file_and_remove)