create a function pair_from_range(a,b): where the function should return a list of all possible tuples (i,j) within a range given certain conditions

Example:

if a=2 and b =5

the function should return

[(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)]

and the following rules should be considered

a <=i , j <=b , i

The order of the tuples inside the list doesn't matter