my $ua = Mojo::UserAgent->new();
$ua->transactor->name( $useragent );
my $tx = $ua->build_tx( GET => $url );
#$tx->res->max_message_size( 0 );
#open my $fh, '>:raw', $file or die $!;
#$tx->res->content->on( read => _return_callback( $fh ) );
#$ua->start( $tx );
#close $fh;