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function loadAsync(e,t){var a,n=!1;a=document.createElement("script"),a.type="text/javascript",a.src=e,a.onreadystatechange=function(){n||this.readyState&&"complete"!=this.readyState||(n=!0,"function"==typeof t&&t())},a.onload=a.onreadystatechange,document.getElementsByTagName("head")[0].appendChild(a)}