Install Python3.6 or Python3.7 in Ubuntu 20.04; ImportError: libpython3.6m.so.1.0: cannot open shared object file

Ubuntu 20.04 has Python 3.8 by default. 
See below to install Python 3.6 or 3.7

sudo -E add-apt-repository ppa:deadsnakes/ppa
sudo apt-get update
sudo apt-get install python3.6
sudo apt-get install -y libpython3.6-dev

Install like above if you get below error

ImportError: libpython3.6m.so.1.0: cannot open shared object file: No such file or directory

Debugging Python with pudb

1. Install pudb pip package..

 $ pip install pudb

2. Add the following statement in python code.

import pudb; pudb.set_trace()

3. Or, Launch the debugger like below

$ python -m pudb my_script.py