import math


def convert_bytes(size):
    """Make a human readable size."""
    label = ('B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB')
    try:
        i = int(math.floor(math.log(size, 1024)))
    except ValueError:
        i = 0
    p = math.pow(1024, i)
    readable_size = round(size/p, 2)
    return '{}{}'.format(readable_size, label[i])