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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def option(self, *args, **kwargs):
 """ Registers a click.option which falls back to a configmanager Item if user hasn't provided a value in the command line. Item must be the last of ``args``. Examples:: config = Config({'greeting': 'Hello'}) @click.command() @config.click.option('--greeting', config.greeting) def say_hello(greeting):
 click.echo(greeting) """

        args, kwargs = _config_parameter(args, kwargs)
        return self._click.option(*args, **kwargs)