MFP waf str buffer error

Traceback (most recent call last):
  File "setup.py", line 15, in <module>
    version = '0.05_' + git_version(),
  File "setup.py", line 11, in git_version
    vers = shcall("git show --oneline").split('\n')[0].split(' ')[0]
TypeError: Type str doesn't support the buffer API