Tag 0.3.3 points to incorrect version in code, along with Python 3 compatibility issues

[kdipippo]

The latest release for this was created in 2017 with version 0.3.3: https://github.com/pybrain/pybrain/releases/tag/0.3.3
However, browsing the codebase, the setup.py had the version 0.3.1 baked in.
https://github.com/pybrain/pybrain/blob/882cf66a89b6b6bb8112f41d200c55461464aa06/setup.py

This doesn't matter all that much, but prior fixes to run PyBrain on newer versions (i.e. the solution in #201 to instead run python3 -m pip install https://github.com/pybrain/pybrain/archive/0.3.3.zip) are showing issues that have been addressed in later commits. For example:

from pybrain.datasets import SequentialDataSet

results in

Traceback (most recent call last):
  File "main.py", line 4, in <module>
    from pybrain.datasets import SequentialDataSet
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pybrain/__init__.py", line 1, in <module>
    from pybrain.structure.__init__ import *
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pybrain/structure/__init__.py", line 2, in <module>
    from pybrain.structure.modules.__init__ import *
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pybrain/structure/modules/__init__.py", line 2, in <module>
    from pybrain.structure.modules.gate import GateLayer, DoubleGateLayer, MultiplicationLayer, SwitchLayer
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pybrain/structure/modules/gate.py", line 10, in <module>
    from pybrain.tools.functions import sigmoid, sigmoidPrime
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pybrain/tools/functions.py", line 4, in <module>
    from scipy.linalg import inv, det, svd, logm, expm2
ImportError: cannot import name 'expm2' from 'scipy.linalg' (/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/scipy/linalg/__init__.py)

This issue was addressed in 5602313

[kdipippo]

As a workaround for others, pip allows for a way to install dependencies based on commit hashes. For downloading the repo from the latest commit: dcdf32b

python3 -m pip install git+ssh://git@github.com/pybrain/pybrain.git@dcdf32ba1805490cefbc0bdeb227260d304fdb42

You can also add this as part of a requirements.txt file, i.e.:

mido==1.2.9
MIDIUtil==1.2.1
numpy==1.18.4
scipy==1.4.1
git+ssh://git@github.com/pybrain/pybrain.git@dcdf32ba1805490cefbc0bdeb227260d304fdb42