tests/readlink.py

py3: conditionalize the raise statement

raise E,V,T is not acceptable in Python 3, thats is conditionalized.
Moreover this will result in syntax error so we have to use exec() to
execute this. Related PEP- https://www.python.org/dev/peps/pep-3109/#id14

My implementation is motivated from the six implementation except they are
defining a new function exec_() to prevent adding an extra frame AFAIK :)

https://bitbucket.org/gutworth/six/src/ca4580a5a648/six.py#six.py-680

#!/usr/bin/env python

from __future__ import absolute_import, print_function

import errno
import os
import sys

for f in sys.argv[1:]:
    try:
        print(f, '->', os.readlink(f))
    except OSError as err:
        if err.errno != errno.EINVAL:
            raise
        print(f, '->', f, 'not a symlink')

sys.exit(0)