anchor.diff:  
   
   # copy TRex client API library
  -ARG TREX_VERSION=v2.00
  +ARG TREX_VERSION=v2.20
   ARG TREX_TMP_PATH=/tmp/trex
   ARG TREX_WEB_URL=http://trex-tgn.cisco.com/trex/release
   ENV TREX_CLIENT_LIB=/opt/trex_client/stl
  
positive.code:     && apt-get autoremove \
      && apt-get clean
  
  
  # need to specify path to Ixia client library and
  # copy ixia files where X.XX is Ixia version
  
negative.code: ' > /root/requirements.txt && pip install --upgrade -r /root/requirements.txt && rm /root/requirements.txt && rm -rf /root/.cache/pip
  
  
  ARG TAF_ROOT=/root/taf
  # copy TAF repo to docker image
  COPY /  $TAF_ROOT/
  