Create a function that takes a list of numbers and return its median. If the input list is even length, take the average of the two medians, else, take the single median.
median([2, 5, 6, 2, 6, 3, 4]) ➞ 4
median([21.4323, 432.54, 432.3, 542.4567]) ➞ 432.4
median([-23, -43, -29, -53, -67]) ➞ -43