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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 read_prototxt(fname):
 """Return a caffe_pb2.NetParameter object that defined in a prototxt file """

    proto = caffe_pb2.NetParameter()
    with open(fname, 'r') as f:
        text_format.Merge(str(f.read()), proto)
    return proto