max value in list

[Terry Reedy]

"C GIllespie" <csgcsg39 at hotmail.com> wrote in message
news:c7te26$8q1$1 at ucsnew1.ncl.ac.uk...
> Dear all,
>
> I have a few lists. What's the best way of finding the maximum number of
all
> the lists.
>
> For example,
>
> [2,3,4],[1,2,3],[4,7]
>
> The max is 7.

Sidestepping 'best' which may depend on context, a general 'good' way is

>>> lists = [2,3,4],[1,2,3],[4,7]
>>> max([max(l) for l in lists])
7

Terry J. Reedy