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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 _find_protocol_error(tb, proto_name):
 """Return the FrameInfo for the lowest frame in the traceback from the protocol. """

    tb_info = traceback.extract_tb(tb)
    for frame in reversed(tb_info):
        if frame.filename == proto_name:
            return frame
    else:
        raise KeyError