use Aspect;
my $pcut = call qr/LWP::UserAgent::send_request/;
before {
    my $ctx = shift;
    print "req================\n";
    print $ctx->params->[1]->as_string;

} $pcut;

after {
    my $ctx = shift;
    print "resp----------------\n";
    print $ctx->return_value->headers->as_string;
    print "==================\n";
} $pcut;

use WWW::Mechanize;
my $m = WWW::Mechanize->new;
$m->get("http://www.google.com");