Added the ability to specify a post release.

Dockerfile

@@ -39,7 +39,7 @@ RUN pyenv install 3.5.10 && \
     pyenv install pypy3.6-7.3.1 && \
     pyenv global 3.9.0
 RUN /.pyenv/versions/3.9.0/bin/python3.9 -m pip install --upgrade pip
-RUN pip install tox
+RUN pip install tox twine
 
 RUN mkdir -p /usr/src/ibapi && \
     chmod a+rwx -R /usr/src/ibapi && \

src/ibapi/__init__.py

@@ -8,11 +8,14 @@ Copyright (C) 2019 Interactive Brokers LLC. All rights reserved. This code is su
 VERSION = {
     'major': 9,
     'minor': 81,
-    'micro': 1}
+    'patch': 1,
+    'extra': 1}
 
 
 def get_version_string():
-    version = '{major}.{minor}.{micro}'.format(**VERSION)
+    version = '{major}.{minor}.{patch}-{extra}'.format(**VERSION)
+    if( VERSION['extra'] <= 0):
+        version = '{major}.{minor}.{patch}'.format(**VERSION)
     return version
 
 __version__ = get_version_string()