def warnpy3k(message, category=None, stacklevel=1):
 if sys.py3kwarning:
  if (category is None):
   category = DeprecationWarning
  warn(message, category, (stacklevel + 1))

def warnpy3k ( message , category = None , stacklevel = 1 ) : if sys . py3kwarning : if ( category is None ) : category = DeprecationWarning warn ( message , category , ( stacklevel + 1 ) )
issue a deprecation warning for python 3 .