Fix training image dockerfile

netcat is moved to one of traditional or openbsd
in ubuntu latest.
Openbsd variant is selected.

Dockerfile.training

@@ -16,16 +16,16 @@ ARG enable_qa=true
 RUN if [ "${base_os}" = "alpine" ] ; then apk update ; elif [ "${base_os}" = "ubuntu" ] ; then apt-get update ; fi
 
 # Installation
-RUN if [ "${base_os}" = "alpine" ] ; then apk add dos2unix ; elif [ "${base_os}" = "ubuntu" ] ; then apt-get install -y dos2unix netcat ; fi
+RUN if [ "${base_os}" = "alpine" ] ; then apk add dos2unix ; elif [ "${base_os}" = "ubuntu" ] ; then apt-get install -y dos2unix netcat-openbsd ; fi
 
 ## Installation for questions & answers (langchain & OpenAI)
-RUN if [ "${enable_qa}" = "true" -a "${base_os}" = "alpine" ] ; then apk add python3.9 py3-pip python3-dev ; fi
-RUN if [ "${enable_qa}" = "true" -a "${base_os}" = "ubuntu" ] ; then apt-get install -y python3.9 python3-pip ; fi
+RUN if [ "${enable_qa}" = "true" -a "${base_os}" = "alpine" ] ; then apk add python3 py3-pip python3-dev ; fi
+RUN if [ "${enable_qa}" = "true" -a "${base_os}" = "ubuntu" ] ; then apt-get install -y python3 python3-pip python3-venv ; fi
 
-RUN if [ "${enable_qa}" = "true" -a "${base_os}" = "alpine" ] ; then pip3 install torch -f https://download.pytorch.org/whl/torch_stable.html ; fi
+RUN if [ "${enable_qa}" = "true" -a "${base_os}" = "alpine" ] ; then python3 -m venv /venv && source /venv/bin/activate && pip3 install torch -f https://download.pytorch.org/whl/torch_stable.html ; fi
 
 # Why split pip3 installed modules: https://github.com/pypa/pip/issues/1386
-RUN if [ "${enable_qa}" = "true" ] ; then pip3 install "langchain==0.0.138" "unstructured==0.5.12" && pip3 install "chromadb==0.3.21" "tiktoken==0.3.3" && pip3 install "openai==0.27.4" ; fi
+RUN if [ "${enable_qa}" = "true" ] ; then python3 -m venv /venv && source /venv/bin/activate && pip3 install "langchain==0.0.138" "unstructured==0.5.12" && pip3 install "chromadb==0.3.21" "tiktoken==0.3.3" && pip3 install "openai==0.27.4" ; fi
 
 # Cleanup
 RUN if [ "${base_os}" = "alpine" ] ; then rm -rf /var/cache/apk/* ; elif [ "${base_os}" = "ubuntu" ] ; then apt-get clean ; fi