my $obj = Your::Module->new($username, $password);

##</code><code>##

use File::HomeDir;
use File::Spec;
use Test::More;

my $creds = File::Spec->catfile(
  File::HomeDir->my_home,
  '.your_module.json',
  );
plan skip_all => 'Cannot test without ~/.your_module.json'
  unless -f $creds;