docs: def disable(commanddict, modulename):
    """
    <Purpose>
      Disables a module and removes its commands from the seash commanddict.
  
    <Arguments>
      modulename: The module to disable.
  
    <Side Effects>
      All commands inside the specified module will be removed from the seash
      commanddict.
  
      A file (modulename.disabled) will be created under /modules/ indicating that
      this module has been disabled.
  
    <Exceptions>
      Exceptions raised by merge_commanddict()
  
    <Returns>
      None
    """
    # Is this an installed module?
    if not modulename in module_data:
      raise seash_exceptions.UserError("Error, module '"+modulename+"' is not installed")
    
    # Is this module enabled?
    if not _is_module_enabled(modulename):
      raise seash_exceptions.UserError("Module is not enabled.")
  
    remove_commanddict(commanddict, module_data[modulename]['command_dict'])
    cleanup(modulename)
  
    # We mark this module as disabled by adding a modulename.disabled file.
    open(MODULES_FOLDER_PATH + os.sep + modulename + ".disabled", 'w')