Usually, devtest is run via make (or ninja), and will use the correct
Python interpreter. When running directly on the command line, it is
important to pick the right Python interpreter so it will work with the
Python API.
Here, we change the default interpreter from Python 2 to 3, because
that's the more common version, and will be the only option for upcoming
UHD 4.0 anyway.
python3+ dropped has_key function on dictionary. In order to make it
compatible, we need to use 'in' keyword.
Signed-off-by: Trung.Tran<trung.tran@ettus.com>
