Problem with example sine-wave

[Roberto Garcìa Vèlez]

I have problems trying to run the following example, please someone can help  
me 

      
ubuntu@ubuntu-VirtualBox:~/nupic$ $NUPIC/scripts/run_swarm.py 
/home/ubuntu/nupic/sine-tutorial/search_def.json 
Traceback (most recent call last):
  File "/home/ubuntu/nupic/scripts/run_swarm.py", line 187, in <module>
    runPermutations(sys.argv[1:])
  File "/home/ubuntu/nupic/scripts/run_swarm.py", line 178, in runPermutations
    fileArgPath, optionsDict, outputLabel, permWorkDir)
  File 
"/home/ubuntu/.local/lib/python2.7/site-packages/nupic/swarming/permutations_runner.py",
 line 305, in runWithJsonFile
    expJsonConfig = json.loads(jsonFile.read())
  File 
"/home/ubuntu/.local/lib/python2.7/site-packages/nupic/swarming/object_json.py",
 line 163, in loads
    json.loads(s, object_hook=objectDecoderHook, **kwargs))
  File "/usr/lib/python2.7/json/__init__.py", line 351, in loads
    return cls(encoding=encoding, **kw).decode(s)
  File "/usr/lib/python2.7/json/decoder.py", line 366, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python2.7/json/decoder.py", line 384, in raw_decode
    raise ValueError("No JSON object could be decoded")
ValueError: No JSON object could be decoded


Thanks,
Roberto