code: def get_command(self):
          
          cmd = None
          count = len(self.command_list)
          if count > 0:
              cmd = self.command_list.pop(0)
          ## If that was the last line, turn off lines_pending
          if count == 1:
              self.cmd_ready = False
          return cmd
docs: Get a line of text that was received from the DE. The class's
          cmd_ready attribute will be true if lines are available.