TDA4VM: edgeai-tidl-tool - Failed to create docker image

Hi,

Getting following error while creating the docker image for edgeai-tidl-tool.

Source : https://github.com/TexasInstruments/edgeai-tidl-tools/blob/master/docs/advanced_setup.md#docker-based-setup-for-x86_pc 

(base) che7@che7-w10142:~/srinivasuluCharupally/generate_artifacts_tda4vm/docker-edgeai-tidl/edgeai-tidl-tools$ sudo docker build -f Dockerfile -t x86_ubuntu_18 .
Sending build context to Docker daemon   27.9MB
Step 1/11 : ARG REPO_LOCATION=''
Step 2/11 : FROM ${REPO_LOCATION}ubuntu:18.04
manifest for ubuntu:18.04 not found
(base) che7@che7-w10142:~/srinivasuluCharupally/generate_artifacts_tda4vm/docker-edgeai-tidl/edgeai-tidl-tools$sudo docker build --build-arg REPO_LOCATION=artifactory.itg.ti.com/docker-public/library/ --build-arg USE_PROXY=ti  -f Dockerfile -t x86_ubuntu_18 .
Sending build context to Docker daemon   27.9MB
Step 1/11 : ARG REPO_LOCATION=''
Step 2/11 : FROM ${REPO_LOCATION}ubuntu:18.04
Get https://artifactory.itg.ti.com/v2/: dial tcp: lookup artifactory.itg.ti.com: no such host

it's bit urgent, could you help me ?