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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 _validate_callback(callback):
 """Checks if the specified callback is callable and accepts a kwargs param. Args: callback (obj):
 Any object or a list of objects that can be called. e.g. <function say_hello at 0x101234567> Raises: SlackClientError: The specified callback is not callable. SlackClientError: The callback must accept keyword arguments (**kwargs). """


        cb_name = callback.__name__ if hasattr(callback, "__name__") else callback
        if not callable(callback):
            msg = "The specified callback '{}' is not callable.".format(cb_name)
            raise client_err.SlackClientError(msg)
        callback_params = inspect.signature(callback).parameters.values()
        if not any(
            param for param in callback_params if param.kind == param.VAR_KEYWORD
        ):
            msg = "The callback '{}' must accept keyword arguments (**kwargs).".format(
                cb_name
            )
            raise client_err.SlackClientError(msg)