add python compatibility module

Issue-ID: DOC-823

Change-Id: I1abb4777f5eb8b01efee0e1807b4f2f3e0cfe04e
Signed-off-by: thmsdt <thomas.kulik@telekom.de>
diff --git a/docs/requirements-docs.txt b/docs/requirements-docs.txt
index ba3e0ec..097282b 100644
--- a/docs/requirements-docs.txt
+++ b/docs/requirements-docs.txt
@@ -4,4 +4,5 @@
 sphinxcontrib-seqdiag # BSD
 sphinxcontrib-swaggerdoc
 sphinxcontrib-spelling
-sphinxcontrib-plantuml
\ No newline at end of file
+sphinxcontrib-plantuml
+six