如何解析protobuf文件中缺少引号的字符串字段?

我试图解析一个protobuf文件,其中一个字段是一个没有引号的字符串。因此,我使用的解析器将该字段读取为int。我想提取实际字符串。

在下面的示例中,如何将此字段(类型)解析为字符串“卷积”,而不是4?

>>> import numpy as np
>>> import sys, os
>>> import argparse
>>> import caffe_quant_pb2 as cq
>>> from google.protobuf import text_format
>>> f = open('models/vgg/deploy.prototxt', 'r')
>>> net_txt = cq.NetParameter()
>>> text_format.Parse(f.read(), net_txt)
name: "VGG_ILSVRC_16_layers"
layers {
  bottom: "data"
  top: "conv1_1"
  name: "conv1_1"
  type: CONVOLUTION
  convolution_param {
    num_output: 64
    pad: 1
    kernel_size: 3
  }
}
>>> print net_txt.layers[0].name  # works as I expect
conv1_1
>>> print net_txt.layers[0].type  # reads CONVOLUTION as the 'int' 4
4
>>> print type(net_txt.layers[0].type)
<type 'int'>
>>> print str("CONVOLUTION" == net_txt.layers[0].type)
False
>>> print str(net_txt.layers[0].type)
4