how to install tornado for python of different version

Question

I'm using python on my CentOS7 server.
By default, there are python, python2, python2.7.

Then, I do yum install tornado. For now everything works fine.

Now I need to use python3.5 with tornado.

I've downloaded and installed python3.5 with its source code. But when I python3.5 server.py, I get an error:

no module named 'tornado'

I've also tried python3.5 -m pip install tornado but I get an error:

no module named pip

Answer 1

First install pip with ensurepip:

python3.5 -m ensurepip

Then:

python3.5 -m pip install tornado