#-*-coding:utf8;-*-
#qpy:3
#qpy:console

import os
import math 


def convert_size(size_bytes): 
    if size_bytes == 0: 
        return "0B" 
    size_name = ("B", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB") 
    units = int(math.floor(math.log(size_bytes, 1024)))
    power = math.pow(1024, units) 
    size = round(size_bytes / power, 2) 
    return "%s %s" % (size, size_name[units])

def crawl(start_dir):
    for root, _, files in os.walk(start_dir):
        for filename in files:
            yield os.path.join(root, filename)

def clean_dir(directory):
    removed = 0
    for filepath in crawl(directory):
        removed += os.stat(filepath).st_size
        print('removing {}'.format(filepath))
        os.remove(filepath)
    print('\nremoved {}'.format(convert_size(removed)))

clean_dir('sdcard/Download/')