python版本问题

[CrazyMJim]

ERROR: /home/m/kcws/kcws/train/BUILD:1:1: Converting to Python 3: kcws/train/generate_training.py failed: 2to3 failed: error executing command bazel-out/host/bin/external/bazel_tools/tools/python/2to3 --no-diffs --nobackups --write --output-dir bazel-out/local-py3-fastbuild/genfiles/python3/kcws/train --write-unchanged-files ... (remaining 1 argument(s) skipped): com.google.devtools.build.lib.shell.BadExitStatusException: Process exited with status 1.
Target //kcws/train:generate_training failed to build
Use --verbose_failures to see the command lines of failed build steps.

看了之前有人提过python3支持问题，我改了代码后发现还是报python2无法转换成python3，求教