<s>[INST] Python - When to use file vs open What's the difference between file and open in Python?  When should I use which one?  (Say I'm in 2.5)
 [/INST] You should always use open().
As the documentation states:

When opening a file, it's preferable
  to use open() instead of invoking this
  constructor directly. file is more
  suited to type testing (for example,
  writing "isinstance(f, file)").

Also, file() has been removed since Python 3.0.
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