from itertools import product

def frange(x, y, jump):
  while x < y:
    yield x
    x += jump

x1 = frange(0, 10, 0.1)
x2 = frange(0, 10, 0.1)
x3 = frange(0, 10, 0.1)
x4 = frange(0, 10, 0.1)

quadriplets = product(x1, x2, x3, x4)

for a, b, c, d in quadriplets:
    if 2 - abs(a * b) <= 0.01 and \
       3 - abs(a * c) <= 0.01 and \
       4 - abs(a * d) <= 0.01 and \
       5 - abs(b * c) <= 0.01 and \
       6 - abs(b * d) <= 0.01:
        print a, b, c, d
        break