Sitecore Powershell script to add renderings to Product Pages

AddLeftNavAndSocialMedia.ps1

$root = gi master:// -id "{076927BD-FFD2-4658-B522-D836C045CF7D}"
$items = $root | ls -r | ?{$_.TemplateName -eq "ProductPage"}
$leftNavRendering = gi master:\layout\Renderings\Site\Components\LeftNav | New-Rendering -Placeholder "contentMain" 
$socialMediaRendering = gi master:\layout\Renderings\Site\Components\SocialMedia\SocialMediaBar | New-Rendering -Placeholder "contentMain"

foreach($i in $items){
    if($leftNavDsPath){
        clear-variable("leftNavDsPath")
    }
    if($leftNavDs){
        clear-variable("leftNavDs")
    }
    if($sMPath){
        clear-variable("sMPath")
    }
    if($sMDs){
        clear-variable("sMDs")
    }
    $leftNavDsPath = [string]::Format("master:/{0}/Local Assets/Left Nav", $i.Paths.Path)
    $leftNavDs = gi -Path $leftNavDsPath
    $sMPath = [string]::Format("master:{0}/Local Assets/LeftNavSocialMedia", $i.Paths.Path)
    $sMDs = gi -Path $sMPath
    Add-Rendering -Item $i -Rendering $socialMediaRendering -Placeholder "contentMain" -Parameter @{"HideInDesktop"=1; } -Datasource $sMDs.Paths.Path
    Add-Rendering -Item $i -Rendering $leftNavRendering -Placeholder "contentMain" -Parameter @{"HideInDesktop"=1; } -Datasource $leftNavDs.Paths.Path
}