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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 _update_listing_client_kwargs(client_kwargs, max_request_entries):
 """ Updates client kwargs for listing functions. Args: client_kwargs (dict):
 Client arguments. max_request_entries (int):
 If specified, maximum entries returned by request. Returns: dict: Updated client_kwargs """

        client_kwargs = client_kwargs.copy()
        if max_request_entries:
            client_kwargs['num_results'] = max_request_entries
        return client_kwargs