The line is nonsense. Let's take a look at the options we have:
length
is falsy (so0
, an empty list, an empty string, etc.). Python will return the value oflength
because there is no point in looking at the rest of the expression as theand
operator evaluates toFalse
whatever the right-hand side evaluates to. It then testslength or len(string)
and returnslen(string)
.length
is not falsy. Python evaluateslength and length
, resolves that to the value oflength
, then testslength or len(string)
, and becauselength
is truthy, returnslength
. After all,or
will now always resolve toTrue
and there is no point in looking atlen(string)
.
This basically comes down to length = length or len(string)
, the length and length
is a no-op.