Function Get-IPAddressesForName {
<#
.SYNOPSIS
	Get the IP addresses for a hostname, or return the IP address passed in
#>
    [CmdletBinding()]
    [OutputType([System.String])]
    Param(
		[Parameter(Mandatory = $true)]
		[string]$hostname
	)

    if (!$hostname) {
        throw 'must supply a value'
    }
    if (!!($hostname -As [IPAddress])) {
        $hostname;
    } else {
        (Resolve-DnsName -Type A $hostname).IPAddress;
    }
}