parse_args;
validate_opts;
prepare_params;
my ($response_code, $response_content) = SES::call_ses \%params, \%opts;
switch ($response_code) {
    case '200' {              # OK
        print_response $response_content;
        exit  0;
    }
    case '400' { exit  1; }   # BAD_INPUT
    case '403' { exit 31; }   # SERVICE_ACCESS_ERROR
    case '500' { exit 32; }   # SERVICE_EXECUTION_ERROR
    case '503' { exit 30; }   # SERVICE_ERROR
    else       { exit -1; }
}