How can I get 2.x-like sorting behaviour in Python 3.x?

Question

I\'m trying to replicate (and if possible improve on) Python 2.x\'s sorting behaviour in 3.x, so that mutually orderable types like int, float etc.

Answer 1

Not running Python 3 here, but maybe something like this would work. Test to see if doing a "less than" compare on "value" creates an exception and then do "something" to handle that case, like convert it to a string.

Of course you'd still need more special handling if there are other types in your list that are not the same type but are mutually orderable.

from numbers import Real
from decimal import Decimal

def motley(value):
    numeric = Real, Decimal
    if isinstance(value, numeric):
        typeinfo = numeric
    else:
        typeinfo = type(value)

    try:
        x = value < value
    except TypeError:
        value = repr(value)

    return repr(typeinfo), value

>>> print sorted([0, 'one', 2.3, 'four', -5, (2+3j), (1-3j)], key=motley)
[-5, 0, 2.3, (1-3j), (2+3j), 'four', 'one']