pythonic way to free resources

[Chirayu]

this one is nice (by Bengt Richter). but we usually want to handle just one 
or two exception types and let the others pass. might the following work?

     class Finalizer:
         def finalize(self):
             for f in self.__dict__.values():
                 f.close()
         def __del__ (self): self.finalize()

     fin = Finalizer()
     try:
         fin.f1 = f1 = file(...)
         # do stuff with f1
         fin.f2 = f2 = file(...)
         # do stuff with f2
     except IOError, e:
          print "An IO Error prevented success: %s." % e
          if we_need_to_return_here:
              del f
              return
     except Exception, e:
          del f
          raise
     # release all resources successfully allocated and logged
     del f

i guess this sprinkles the code with "del f" (or "f.finalize()") but it 
still looks a lot better than not using a Finalizer class.

or perhaps, with nested try blocks.

     fin = Finalizer()
     try:
         try:
             fin.f1 = f1 = file(...)
             # do stuff with f1
             fin.f2 = f2 = file(...)
             # do stuff with f2
         except IOError, e:
              print "An IO Error prevented success: %s." % e
              if we_need_to_return_here:
                  return
         except Exception, e:
              raise
     finally:
        # release all resources successfully allocated and logged
        del f

ps: would the "del f" would have the possibly minor advantage of 
decrementing the ref counts (or deleting) of all the objects it holds?

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