Running and Quitting
      
      Juypter Lab Interface    
      
      Menu Bar
      
      The Menu Bar at the top of JupyterLab has the top-level menus that
      expose various actions available in JupyterLab along with their
      keyboard shortcuts (where applicable). The following menus are
      included by default.
      
          File: Actions related to files and directories
      such as New, Open, Close, Save, etc. The File menu also includes
      the Quit action used to shutdown the JupyterLab server.
          Edit: Actions related to editing documents and
      other activities such as Undo, Cut, Copy, Paste, etc.
          View: Actions that alter the appearance of
      JupyterLab.
          Run: Actions for running code in different
      activities such as notebooks and code consoles (discussed below).
          Kernel: Actions for managing kernels which, as
      mentioned above, are separate processes for running code.
          Tabs: A list of the open documents and
      activities in the dock panel.
          Settings: Common JupyterLab settings can be
      configured using this menu. There is also an Advanced Settings
      Editor option in the dropdown menu that provides more fine-grained
      control of JupyterLab settings and configuration options.
          Help: A list of JupyterLab and kernel help
      links.
      
    
    First Python Program
          Within the Python 3 window, type
          x = 6 * 7 + 12
          print(x)
    Run code
          Press Shift Enter keys at same time
      Should see 54