in reply to Re^3: LWP: transfer from Python to Perl
in thread LWP: transfer from Python to Perl

You can preserve the underscores with a colon

$request->header(
   ':__Atts' => $ajax_atts,
   ':__Ath'  => $ajax_ath,
   ':__Atcrv'=> $ajax_atcrv);

[download]

see NON-CANONICALIZED FIELD NAMES in HTTP::Headers

poj

In Section Seekers of Perl Wisdom