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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def exists(*paths):
 """ Assert that all given paths exist. :params paths: files/directories to be checked for existence :raises check50.Failure: if any ``path in paths`` does not exist Example usage:: check50.exists("foo.c", "foo.h") """

    for path in paths:
        log(_("checking that {} exists...").format(path))
        if not os.path.exists(path):
            raise Failure(_("{} not found").format(path))