title: All possible sums from lists, only one entry summed per list
body: <p>I'm making a practice program in Python to calculate all the different weights I can put on the rack, with a given set of plates.</p>
  
  <pre><code>def Weights(t=1,f=1,tn=1,tf=1,thf=1,ff=1,b=45):
  
    Max=b+5*t+10*f+20*tn+50*tf+70*thf+90*ff
    Poss=range(b,Max+1,5)
  
    ts=(list((i*5 for i in range(0,t+1))))
    fs=(list((i*10 for i in range(0,f+1))))
    tns=(list((i*20 for i in range(0,tn+1))))
    tfs=(list((i*50 for i in range(0,tf+1))))
    thfs=(list((i*70 for i in range(0,thf+1))))
    ffs=(list((i*90 for i in range(0,ff+1))))
  
  Weights()
  </code></pre>
  
  <p>This leaves me with 6 lists.  To get all the combos, I need to add up one element of a list with one element of each other list.  At this point, it's clearly a linear algebra problem, I just don't know how to express this in Python, especially because I don't want to use plugins (No NumPy)</p>