$list = Get-Content "distributiongroup.txt"
Foreach ($i in $list) {
$i
$grp = get-distributiongroup $i
$manage = $grp.managedby
$newuser = get-user USER
$newmanage = $manage + $newuser
Set-distributiongroup $grp -managedby $newmanage -bypasssecuritygroupmanagercheck
}