Create dictionary based of x items per key from two lists

[rajanbond at gmail.com]

I have two lists 

l1 =  ["a","b","c","d","e","f","g","h","i","j"]
l2 = ["aR","bR","cR"]

l2 will always be smaller or equal to l1

numL1PerL2 = len(l1)/len(l2)

I want to create a dictionary that has key from l1 and value from l2 based on numL1PerL2

So

{
a:aR,
b:aR,
c:aR,
d:bR,
e:bR,
f:bR,
g:cR,
h:cR,
i:cR,
j:cR
}

So last item from l2 is key for remaining items from l1