git clone https://github.com/ShichaoMa/downloader_cluster.git
    sudo python setup.py install

    or

    sudo pip install downloader-cluster

    ubuntu@dev:~$ downloader -h
    usage: downloader.py [-h] {start,reload} ...

    positional arguments:
      {start,reload}
        start         start download a file.
        reload        continue downlaod a file.

    optional arguments:
      -h, --help      how this help message and exit
    Command 'start'
    usage: downloader.py start [-h] [-s SETTINGS] -u URL [-f FILENAME]

    Command 'reload'
    usage: downloader.py reload [-h] [-s SETTINGS] -u URL [-f FILENAME]

#普通下载
        downloader start -u "https://download.jetbrains.8686c.com/python/pycharm-community-2016.2.tar.gz" -f  test.tar.gz
#断点续传(服务器需要提供支持)
        downloader reload -u "https://download.jetbrains.8686c.com/python/pycharm-community-2016.2.tar.gz" -f  test.tar.gz