Partly revert revision 571 because of side effect
Partly revert revision 571 because of side effect

The error is:
  File "/Library/Python/2.7/site-packages/smartcard/__init__.py", line 34, in <module>
    from smartcard.System import listReaders
  File "/Library/Python/2.7/site-packages/smartcard/System.py", line 27, in <module>
    import smartcard.reader.ReaderFactory
  File "/Library/Python/2.7/site-packages/smartcard/reader/ReaderFactory.py", line 34, in <module>
    from smartcard.pcsc.PCSCReader import PCSCReader
  File "/Library/Python/2.7/site-packages/smartcard/pcsc/PCSCReader.py", line 25, in <module>
    from smartcard.CardConnectionDecorator import CardConnectionDecorator
  File "/Library/Python/2.7/site-packages/smartcard/CardConnectionDecorator.py", line 27, in <module>
    from smartcard.CardConnection import CardConnection
  File "/Library/Python/2.7/site-packages/smartcard/CardConnection.py", line 28, in <module>
    from smartcard.Observer import Observer
  File "/Library/Python/2.7/site-packages/smartcard/Observer.py", line 81, in <module>
    "countObservers")
  File "/Library/Python/2.7/site-packages/smartcard/Synchronization.py", line 36, in synchronize
    klass.__dict__[name] = synchronized(val)
TypeError: 'dictproxy' object does not support item assignment

LudovicRousseau/pyscard,LudovicRousseau/pyscard,LudovicRousseau/pyscard,moreati/pyscard,moreati/pyscard,moreati/pyscard