code: def validate_schema(sconf):
      
  
      # verify session_name
      if 'session_name' not in sconf:
          raise exc.ConfigError('config requires "session_name"')
  
      if 'windows' not in sconf:
          raise exc.ConfigError('config requires list of "windows"')
  
      for window in sconf['windows']:
          if 'window_name' not in window:
              raise exc.ConfigError('config window is missing "window_name"')
  
          if 'panes' not in window:
              raise exc.ConfigError(
                  'config window %s requires list of panes' % window['window_name']
              )
  
      return True
docs: Return True if config schema is correct.
  
      Parameters
      ----------
      sconf : dict
          session configuration
  
      Returns
      -------
      bool