[newbie] how to make program suggest to install missing modules

[hugocoolens]

I'd like to add the following to a python-program:

when a module (take rtlsdr as an example) is not installed on the system I'd 
like to ask the program something like:

module rtlsdr is missing, shall I install it? y or n
if n -->sorry but then I can't run this program and quit program
if y -->execute this command:
os.system(sudo pip install pyrtlsdr)

continue program

can anyone here show me how to perform this properly?

thanks in advance
hugo

--- SoupGate-Win32 v1.05
 * Origin: <SpaceSST.BBS.Fidonet<>NNTP.gateway. at .piz.noip.me> (1:249/999)
--- Synchronet 3.15b-Win32 NewsLink 1.92
SpaceSST BBS Usenet <> Fidonet Gateway