def download_setuptools(version=DEFAULT_VERSION, download_base=DEFAULT_URL,<EOL>to_dir=os.curdir, delay=<NUM_LIT:15>):
<EOL>to_dir = os.path.abspath(to_dir)<EOL>try:<EOL><INDENT>from urllib.request import urlopen<EOL><DEDENT>except ImportError:<EOL><INDENT>from urllib2 import urlopen<EOL><DEDENT>tgz_name = "<STR_LIT>" % version<EOL>url = download_base + tgz_name<EOL>saveto = os.path.join(to_dir, tgz_name)<EOL>src = dst = None<EOL>if not os.path.exists(saveto):  <EOL><INDENT>try:<EOL><INDENT>log.warn("<STR_LIT>", url)<EOL>src = urlopen(url)<EOL>data = src.read()<EOL>dst = open(saveto, "<STR_LIT:wb>")<EOL>dst.write(data)<EOL><DEDENT>finally:<EOL><INDENT>if src:<EOL><INDENT>src.close()<EOL><DEDENT>if dst:<EOL><INDENT>dst.close()<EOL><DEDENT><DEDENT><DEDENT>return os.path.realpath(saveto)<EOL>
Download setuptools from a specified location and return its filename

    `version` should be a valid setuptools version number that is available
    as an egg for download under the `download_base` URL (which should end
    with a '/'). `to_dir` is the directory where the egg will be downloaded.
    `delay` is the number of seconds to pause before an actual download
    attempt.