[Documentation] Add python compatibility module

Required to prevent build problems

Issue-ID: DOC-823

Change-Id: I1ff25188642176ac2952d4288dc1550746000d6c
Signed-off-by: thmsdt <thomas.kulik@telekom.de>
diff --git a/docs/requirements-docs.txt b/docs/requirements-docs.txt
index 9c104de..be92e5d 100644
--- a/docs/requirements-docs.txt
+++ b/docs/requirements-docs.txt
@@ -6,3 +6,4 @@
 sphinxcontrib-spelling
 sphinxcontrib-plantuml
 sphinx_toolbox>=3.2.0
+six
\ No newline at end of file