packaging and version fields

mypackage.mypackage.__init__.py

__version__ = '1.2.3'

mypackage.setup.py

from setuptools import setup

setup(
  name='mypackage',
  version='2.3.4',  # this one actually doesn't matter, it's package metadata that is not related to source code
  packages=['mypackage']
)

testing.sh

~/mypackage$ python3 -m venv env
~/mypackage$ source env/bin/activate
# work in a new virtual env in order to be able to install and manipulate stuff

(env) ~/mypackage$ python -c "import mypackage; print(mypackage.__version__)"
1.2.3
# python puts the call directory into sys.path, which is why it can find the file even though it isn't installed

(env) ~/mypackage$ cd ..
(env) ~$ python -c "import mypackage; print(mypackage.__version__)"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
ImportError: No module named mypackage
# the expected erronous output. when the package isn't installed, this is what should happen 

(env) ~$ cd mypackage
(env) ~/mypackage$ python setup.py install
(env) ~/mypackage$ cd ..  # go out again, so that we don't just run the local sources
(env) ~$ python -c "import mypackage; print(mypackage.__version__)"
1.2.3
# it works

(env) ~$ pip uninstall -y mypackage
[...]  # bla bla uninstalling
(env) ~$ cd mypackage
(env) ~/mypackage$ pip install .
(env) ~/mypackage$ cd ..  # go out again, so that we don't just run the local sources
(env) ~$ python -c "import mypackage; print(mypackage.__version__)"
1.2.3
# it works