JSForce Prototypes not working

Keep getting the following error when i run the three code blocks. The errors seem to show for some reason that prototypes aren't be loaded in some cases. I'm running this NodeJS (As a VSCode Extension). Any thoughts?

error TypeError: this._createSingle is not a function extension.js:65 at Tooling.Connection.insert.Connection.create (/Users/michaelgarfinkel/Documents/forcecompiler/node_modules/jsforce/lib/connection.js:727:12) at compile (/Users/******/Documents/*******/extension.js:58:29) at /Users/michaelgarfinkel/Documents/forcecompiler/extension.js:126:17 at /Users/michaelgarfinkel/Documents/forcecompiler/node_modules/jsforce/lib/promise.js:72:9 at _combinedTickCallback (internal/process/next_tick.js:73:7) at process._tickCallback (internal/process/next_tick.js:104:9)

I run this first

conn = new jsforce.Connection({
    // you can change loginUrl to connect to sandbox or prerelease env.
    loginUrl: 'https://test.salesforce.com',
    version: '43.0'
});

this second

conn.login(username, password, function (err, userInfo) {
            if (err) {
                console.error(err);
                reject(err);
            } else {
                // Now you can get the access token and instance URL information.
                // Save them to establish connection next time.
                console.log(conn.accessToken);
                console.log(conn.instanceUrl);
                // logged in user property
                console.log("User ID: " + userInfo.id);
                console.log("Org ID: " + userInfo.organizationId);
                // ...
                console.log('conn', conn);            
}
        });

And this third

return conn.tooling.sobject('ApexClass').create({
    body: apexBody
}, function (err, res) {
    if (err) { return console.error(err); }
    console.log(res);
});

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