unable to execute jquery in chrome console code example

Example 1: can we import jquery library from developer tools

var script = document.createElement('script');script.src = "https://code.jquery.com/jquery-3.4.1.min.js";document.getElementsByTagName('head')[0].appendChild(script);

Example 2: how to use jquery in chrome dev tools

var jq = document.createElement('script');
jq.src = "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js";
document.getElementsByTagName('head')[0].appendChild(jq);
// ... give time for script to load, then type (or see below for non wait option)
jQuery.noConflict();