Can someone help me with this error while posting data to RPC server

[Kiran Sandeep]

get_ab_metadata {"id":17,"method":"get_ab_metadata","params":{"guid":"e4ab8c83-2e62-48a3-9866-96223787be8a"}}

Traceback (most recent call last):

  File "clutchrpc/app.py", line 84, in handle_rpc

    return func(request_json, **(request_json.get('params') or {}))

  File "clutchrpc/ab.py", line 53, in get_ab_metadata

    simplejson.loads(variation['data']))

  File "/usr/lib/python2.6/site-packages/simplejson-2.6.1-py2.6.egg/simplejson/__init__.py", line 451, in loads

    return _default_decoder.decode(s)

  File "/usr/lib/python2.6/site-packages/simplejson-2.6.1-py2.6.egg/simplejson/decoder.py", line 406, in decode

    obj, end = self.raw_decode(s)

  File "/usr/lib/python2.6/site-packages/simplejson-2.6.1-py2.6.egg/simplejson/decoder.py", line 426, in raw_decode

    raise JSONDecodeError("No JSON object could be decoded", s, idx)

JSONDecodeError: No JSON object could be decoded: line 1 column 0 (char 0)

Thanks in advance!