[Tutor] evaluating AND

[Orest Kozyar]

Given a variable x that can either be None or a tuple of two floats [i.e.
(0.32, 4.2)], which syntax is considered most appropriate under Python
coding standards?

if x and x[0] > 0:
	pass

=====OR=====

if x:
	if x[0] > 0:
		pass


In the first, I'm obviously making the assumption that if the first
condition evaluates to false, then the second condition won't be evaluated.
But, is this a good/valid assumption to make?  Is there a more appropriate
design pattern in Python?

Thanks!
Orest