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I think that the fact that Nick got the code to close multiple files wrong underlines that it is difficult to get right currently. Nick's code
 try:
 files = [open(fname) for fname in names]
 # ...
 finally:
 for f in files:
 f.close()
only closes the files if all of them were opened successfully. Moreover, `file.close()` can fail for various reasons, which would result in all remaining files being left open. When we fix both problems, the code becomes
 try:
 files = []
 for fname in names:
 files.append(open(fname))
 # ...
 finally:
 for f in files:
 try:
 f.close()
 except IOError:
 pass
I think everyone will agree that the version using 'CleanupManager' is nicer. To be fair, we should note that the need to open many files simultaneously is not very common -- usually, we can make to with opening the files one by one.