Error when downloading files from intermediate folder

[jling11]

When I try to download files:
citrination get_files -k API_KEY -d 153238

I get an error when it tries to download files in an intermediate directory:

Downloading: Sample16.json Bytes: 16317655 To: citrination-files-1507568281/version_159257
Downloading: Sample3.json Bytes: 15997793 To: citrination-files-1507568281/version_159257
Downloading: Sample1.json Bytes: 16301001 To: citrination-files-1507568281/version_159257
16301001 [100.00%]
Traceback (most recent call last):
File "/Users/julialing/anaconda/bin/citrination", line 11, in
sys.exit(main())
File "/Users/julialing/anaconda/lib/python2.7/site-packages/citrination/main.py", line 24, in main
app.run()
File "/Users/julialing/anaconda/lib/python2.7/site-packages/cli/app.py", line 245, in run
return self.post_run(returned)
File "/Users/julialing/anaconda/lib/python2.7/site-packages/cli/app.py", line 241, in run
returned = self.main(*args)
File "/Users/julialing/anaconda/lib/python2.7/site-packages/citrination/command_router.py", line 33, in main
app.run()
File "/Users/julialing/anaconda/lib/python2.7/site-packages/cli/app.py", line 245, in run
return self.post_run(returned)
File "/Users/julialing/anaconda/lib/python2.7/site-packages/cli/app.py", line 241, in run
returned = self.main(*args)
File "/Users/julialing/anaconda/lib/python2.7/site-packages/citrination/commands/get_files.py", line 34, in main
download_file(file['url'], file['filename'], versioned_dir_name)
File "/Users/julialing/anaconda/lib/python2.7/site-packages/citrination/util.py", line 32, in download_file
f = open('' + target_dir + '/' + file_name, 'wb')
IOError: [Errno 2] No such file or directory: u'citrination-files-1507568281/version_159257/Qchi_plots/Sample16_2thin_24x24_t30_0003_Qchi.png'