check path.exists() with a "converted" path

[Alessandro]

Hi, I'm a python newbie with a problem too hard to tackle.

I have a string defining a path, were all the spaces have been
converted to underscores.
How can I find if it corresponds to a real path?

e.g. a string like '/some/path_to/directory_1/and_to/directory_2'
with a real path: '/some/path_to/directory 1/and_to/directory 2'

notice that the real path can contain BOTH spaces and underscores.

How can I feed it to os.path.exists() ???

thanks
  alessandro