tlist = [0.0, 0.07, 0.13, 0.15, 0.2, 0.22]
newlist = [0.0, 0.04, 0.08, 0.12, 0.16, 0.2]

def getrange(x):
    for i in range(len(tlist)):
        if tlist[i] > x:
            return tlist[max(0, i - 1)], tlist[i]
[getrange(x) for x in newlist]
getting a boundary of an item from another list