docs: def print_plugins(self):
          """Print the available plugins."""
          width = console_width()
          line = Style.BRIGHT + '=' * width + '\n'
          middle = int(width / 2)
          if self.available_providers:
              print(line + ' ' * middle + 'PROVIDERS')
              for provider in sorted(self.available_providers.values(),
                                     key=lambda x: x.identifier):
                  provider().print()
                  print()
          if self.available_checkers:
              print(line + ' ' * middle + 'CHECKERS')
              for checker in sorted(self.available_checkers.values(),
                                    key=lambda x: x.identifier):
                  checker().print()
                  print()