docker: ubuntu14.04 unable install redis-server

gistfile1.txt

# apt-get install python-software-properties
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package python-software-properties is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
However the following packages replace it:
  software-properties-common

E: Package 'python-software-properties' has no installation candidate
# apt-get install software-properties-common
# add-apt-repository ppa:rwky/redis
# apt-get update
# apt-get install redis-server