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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 green_callback(fn, obj=None, green_mode=None):
 """Return a green verion of the given callback."""

    executor = get_object_executor(obj, green_mode)

    @wraps(fn)
    def greener(*args, **kwargs):
        return executor.submit(fn, *args, **kwargs)

    return greener