objects are required. They are syntactically restricted to a single
expression. Semantically, they are just syntactic sugar for a normal
function definition. Like nested function definitions, lambda forms
-cannot reference variables from the containing scope, but this can be
-overcome through the judicious use of default argument values:
+can reference variables from the containing scope:
\begin{verbatim}
>>> def make_incrementor(n):
-... return lambda x, incr=n: x+incr
+... return lambda x: x + n
...
>>> f = make_incrementor(42)
>>> f(0)
42
>>> f(1)
43
->>>
\end{verbatim}