'Open a browser displaying this session.
Args:
obj (LayoutDOM object, optional) : a Layout (Row/Column),
Plot or Widget object to display. The object will be added
to the session\'s document.
browser (str, optional) : browser to show with (default: None)
For systems that support it, the **browser** argument allows
specifying which browser to display in, e.g. "safari", "firefox",
"opera", "windows-default" (see the ``webbrowser`` module
documentation in the standard lib for more details).
new (str, optional) : new file output mode (default: "tab")
For file-based output, opens or raises the browser window
showing the current output file.  If **new** is \'tab\', then
opens a new tab. If **new** is \'window\', then opens a new window.'

def show(self, obj=None, browser=None, new='tab'):

    if (obj and (obj not in self.document.roots)):
        self.document.add_root(obj)
    show_session(session=self, browser=browser, new=new)
