Python 3: cast map() result to list

On Python 3, map() returns a generator, not a list. Cast explicitly the result
of map() to a list to get a list on Python 2 and Python 3.

The cast is useless in Python 2, but it doesn't hurt performances: it's just a
unit test.

Change-Id: I87486b7dbc42507a6fd7886748a2e09735b6fc5b
Python 3: Fix tests using temporary text files

Use mode "w" instead of the default mode "wb+" to get text file instead of
binary file on Python 3.

Change-Id: I2efe8d926309cfcd5ffe4ea963c11799773def73
Merge "Python 3: Fix tests using temporary text files"
Merge "Python 3: cast map() result to list"