Python分段下载文件，python分段,下载较大文件时分段下载会

下载较大文件时分段下载会加速下载过程，几乎所有下载软件都有类似的特性。在python中如何实现分段下载文件呢？```python

import urllib2req = urllib2.Request('http://www.python.org/')

下载19000到20000字节的片段

req.headers['Range'] = 'bytes=%s-%s' % (19000, 20000)f = urllib2.urlopen(req)pagerange = f.headers.get('Content-Range')print pagerangebytes 19000-19189/19190print repr(f.read())'</div>\n\tCopyright &amp;copy; 1990-2012, <a href=\'/psf/\'>Python Software Foundation</a><br/>\n\t<a href="/about/legal">Legal Statements</a>\n </div>\n\n\n </div>\n </div>\n</body>\n</html>\n\n\n\n\n\n\n'

```