Boni's questions

I have installed python 2.7 and python 3.7 in my ubuntu 18.04 but when i

type python it shows

  Command 'python' not found, but can be installed with:

  sudo apt install python3       
  sudo apt install python        
  sudo apt install python-minimal

  You also have python3 installed, you can run 'python3' instead.

but i already installed python.

I am installing Nvidia driver 340 in ubuntu 18.04 but i got this error

dpkg-divert: error: rename involves overwriting '/usr/lib/x86_64-linux- 
gnu/libGL.so.1.distrib' with
different file '/usr/lib/x86_64-linux-gnu/libGL.so.1', not allowed

Thanks in advance