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use strict;
use warnings;
use Date::Parse;

<some more code here>

$dashboardAlarmStartTime = $dashboardAlarm->startTime;
print "dashboardAlarmStartTime: " . $dashboardAlarmStartTime . "\n";
$maxDashboardAlarmForGroupStartTime = $maxDashboardAlarmForGroup->startTime;
print "maxDashboardAlarmForGroupStartTime: " . $maxDashboardAlarmForGroupStartTime . "\n";
my $timeDiff = str2time($dashboardAlarmStartTime) - str2time($maxDashboardAlarmForGroupStartTime);
print "timeDiff: " . $timeDiff . "\n";