some errors if he is ending

[peseta3]

ok I get the next Problem
What means this?

transmitting...
Binary before pwm encoding:
1000
Binary after pwm encoding:
1000111011101110

Done.
Exception in thread Thread-2 (most likely raised during interpreter shutdown):
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 801, in __bootstrap_inner
  File "/usr/lib/python2.7/threading.py", line 754, in run
  File "/usr/local/lib/python2.7/dist-packages/rflib/chipcon_usb.py", line 475, in runEP5_recv
<type 'exceptions.AttributeError'>: 'NoneType' object has no attribute 'USBError'
root@kali:~/rfcat_150225/rfpwnon#