Update calc_release_version.py for Python3
Update calc_release_version.py for Python3

if it does not find the BUILD_VERSION file, it will try to create a version with calc_release_version.py script, and it will give script exception because of the current print usage that do not support python3 and some encoding errors.

Error samples;
- SyntaxError: Missing parentheses in call to 'print'. Did you mean print('Debugging output enabled.')?
- TypeError: must be str, not bytes
- TypeError: can't concat str to bytes

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