How to get "no distance and clean" version ?

[LuisBL]

I try to release a new version: 5.0:
so I tag:

git tag -a -m 'test tag' 5.0

git describe is:

$ git describe --long
5.0-0-g0386a2c
$

I'm expecting as explain in : setuptools_scm
to get:
no distance and clean: {tag}
but I get:

distance and clean:
    {next_version}.dev{distance}+n{revision hash}

As you can see::

$ python setup.py install
...
$ ls dist/
Ble-5.1.dev0+ng0386a2c.d20161006-py2.7.egg
$ 

[LuisBL]

Same with a x.y.z version:

$ git tag -a -m 'test' 5.0.0
$ python setup.py install
...
$ ls dist/
dist/Ble-5.0.1.dev0+ng0386a2c.d20161006-py2.7.egg
$

[LuisBL]

My branch was dirty:

git describe --dirty --long