when is 'commands' preferable to 'popen' subprocess?
===

I'm apprenticing into system administration without schooling, so sometimes I'm missing what is elementary information to many others.

I'm attempting to give my stdout line another argument before printing, but I'm not sure which process I should use, and I'm a bit fuzzy on the commands for subprocess if that's what I should be using.  

My current code is: 

    f = open('filelist', 'r')
    searchterm = f.readline()
    f.close()|
    #takes line from a separate file and gives it definition so that it may be callable.
    
    import commands
    commands.getoutput('print man searchterm')

This is running, but not giving me an ouput to the shell.  My more important question is though, am I using the right command to get my preferred process?  Should I be using one of the subprocess commands instead?  I tried playing around with popen, but I don't understand it fully enough to use it correctly.

Ie, I was running 

    subprocess.Popen('print man searchterm') 

but I know without a doubt that's not how you're supposed to run it.  Popen requires more arguments than I have given it, like file location and where to run it (Stdout or stderr).  But I was having trouble making these commands work.  Would it be something like:

    subprocess.Popen(pipe=stdout 'man' 'searchterm')
    #am unsure how to give the program my arguments here.  
  

 I've been researching everywhere, but it is such a widely used process I seem to be suffering from a surplus of information rather than not enough.  Any help would be appreciated, I'm quite new. 

Preemptive thanks for any help. 