Powerful perl paradigm I don't find in python

[me]

On 2016-01-15, Ulli Horlacher <framstag at rus.uni-stuttgart.de> wrote:
> Charles T. Smith <cts.private.yahoo at gmail.com> wrote:
>> while ($str != $tail) {
>>     $str ~= s/^(head-pattern)//;
>>     use ($1);
>> }
>
> use() is illegal syntax in Perl.

Actually it is not. OP is defnitely thinking of `use` as a placeholder for
some general use of the value $1.

In fact, according to the documentation of perl,

    use Module LIST

is equivalent of 

    BEGIN{ require Module; Module->import(LIST); }

For the rusty perl users, the code in `BEGIN` blocks are executed "as soon
as possible", that is before the remaining part of the code, and in order
of definition.

The idea is that you want to import all modules before running the code.