local -r staging_path=$1
  local -r gs_url=$2
  local -r tar=$3
  local -r hash=$4
  local -r basename_tar=$(basename "${tar}")

  #check whether this tar alread exists and has the same hash
  #if it matches, then don't bother uploading it again

  #remote_tar_md5 checks the remote location for the existing tarball and its md5
  #staging_path example gs://kubernetes-staging-PROJECT/kubernetes-devel