Chaining Comparison Operators

Formally, assuming a, b, c, …, y, z are expressions and op1, op2, …, opN are comparison operators, then a op1 b op2 c ... y opN z is equivalent to a op1 b and b op2 c and ... y opN z.

>>> x = 5
>>> 1 < x < 10
True
>>> 10 < x < 20
False
>>> x < 10 < x*10 < 100
True
>>> 10 > x <= 9
True
>>> 5 == x > 4
True
>>> i < flag > j

So the expression below is legal.

>>> 1 < 2 > 0 < 3 < 4 > 2 < 3
True

This feature is welcomed for readability.