Skulpt runit() button conflicting with CodeMirror?

I am making an in-browser (static) Python editor with Skulpt and CodeMirror. Here is the code for it so far:

<!DOCTYPE html>
<html>

<head>

    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js" type="text/javascript">
    </script>
    <script src="http://www.skulpt.org/static/skulpt.min.js" type="text/javascript">
    </script>
    <script src="http://www.skulpt.org/static/skulpt-stdlib.js" type="text/javascript">
    </script>
    <script src="https://www.cs.princeton.edu/~dp6/CodeMirror/lib/codemirror.js" type="text/javascript">
    </script>
    <script src="https://www.cs.princeton.edu/~dp6/CodeMirror/mode/python/python.js" type="text/javascript">
    </script>
    <link href="https://www.cs.princeton.edu/~dp6/CodeMirror/lib/codemirror.css" rel="stylesheet" type="text/css">
    <title></title>
</head>

<body>
    <script type="text/javascript">
        function outf(text) {
            var mypre = document.getElementById("dynamicframe");
            mypre.innerHTML = mypre.innerHTML + text;
        }

        function builtinRead(x) {
            if (Sk.builtinFiles === undefined || Sk.builtinFiles["files"][x] === undefined)
                throw "File not found: '" + x + "'";
            return Sk.builtinFiles["files"][x];
        }

        function runit() {
                var prog = document.getElementById("textbox").value;
                var mypre = document.getElementById("dynamicframe");
                mypre.innerHTML = '';
                Sk.pre = "dynamicframe";
                Sk.configure({
                    output: outf,
                    read: builtinRead
                });
                (Sk.TurtleGraphics || (Sk.TurtleGraphics = {})).target = 'canvas';
                var myPromise = Sk.misceval.asyncToPromise(function() {
                    return Sk.importMainWithBody("<stdin>", false, prog, true);
                });
                myPromise.then(function(mod) {
                        console.log('success');
                    },
                    function(err) {
                        console.log(err.toString());
                    });
            }
            //<![CDATA[
        window.onload = function() {
                CodeMirror.fromTextArea(document.getElementById('textbox'), {
                    mode: {
                        name: "python",
                        version: 2,
                        singleLineStringErrors: false
                    },
                    lineNumbers: true,
                    indentUnit: 4
                });
            } //]]>
    </script>
    <textarea id="textbox" name="textbox"></textarea>
    <br>
    <button onclick="runit()" type="button">Run</button>
    <pre id="dynamicframe"></pre>
    <div id="canvas"></div>
</body>

</html>

With the <button>, I call onclick="runit()" but it does not do anything at all when clicked. I took the skulpt code directly from their website (skulpt.org) and the CodeMirror parts from a fiddle (https://jsfiddle.net/gw0shwok/2/). They seem to conflict each other in some way when I call the runit() function on a button click. Why is this? How can I fix the issue?

A link to my live editor: http://ckdata.neocities.org/python.html

This worked for me:

// Step 1: Declare a variable to hold the editor:
 <script type="text/javascript">
        var editor;
         function outf(text) {...

Then save the codemirror editor when it's created:

 // Step 2 : Save the codemirror object in the editor.
   window.onload = function() {
                editor = CodeMirror.fromTextArea(document.getElementById('textbox'), {
                    mode: {...

Finally use the codemirror API to get the contents of the editor in the runit callback:

function runit() {
            var prog = editor.getDoc().getValue(); // Use codemirror API
            var mypre = document.getElementById("dynamicframe");

This worked for me: here is the output

Here is the entire modified code:

<!DOCTYPE html>
<html>

<head>

    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js" type="text/javascript">
    </script>
    <script src="http://www.skulpt.org/static/skulpt.min.js" type="text/javascript">
    </script>
    <script src="http://www.skulpt.org/static/skulpt-stdlib.js" type="text/javascript">
    </script>
    <script src="https://www.cs.princeton.edu/~dp6/CodeMirror/lib/codemirror.js" type="text/javascript">
    </script>
    <script src="https://www.cs.princeton.edu/~dp6/CodeMirror/mode/python/python.js" type="text/javascript">
    </script>
    <link href="https://www.cs.princeton.edu/~dp6/CodeMirror/lib/codemirror.css" rel="stylesheet" type="text/css">
    <title></title>
</head>

<body>
    <script type="text/javascript">
        var editor;
        function outf(text) {
            var mypre = document.getElementById("dynamicframe");
            mypre.innerHTML = mypre.innerHTML + text;
        }

        function builtinRead(x) {
            if (Sk.builtinFiles === undefined || Sk.builtinFiles["files"][x] === undefined)
                throw "File not found: '" + x + "'";
            return Sk.builtinFiles["files"][x];
        }

        function runit() {
                var prog = editor.getDoc().getValue();
                var mypre = document.getElementById("dynamicframe");
                mypre.innerHTML = '';
                Sk.pre = "dynamicframe";
                Sk.configure({
                    output: outf,
                    read: builtinRead
                });
                (Sk.TurtleGraphics || (Sk.TurtleGraphics = {})).target = 'canvas';
                var myPromise = Sk.misceval.asyncToPromise(function() {
                    return Sk.importMainWithBody("<stdin>", false, prog, true);
                });
                myPromise.then(function(mod) {
                        console.log('success');
                    },
                    function(err) {
                        console.log(err.toString());
                    });
            }
            //<![CDATA[
        window.onload = function() {
                editor = CodeMirror.fromTextArea(document.getElementById('textbox'), {
                    mode: {
                        name: "python",
                        version: 2,
                        singleLineStringErrors: false
                    },
                    lineNumbers: true,
                    indentUnit: 4
                });
            } //]]>
    </script>
    <textarea id="textbox" name="textbox"></textarea>
    <br>
    <button onclick="runit()" type="button">Run</button>
    <pre id="dynamicframe"></pre>
    <div id="canvas"></div>
</body>

</html>