pyenv global 设置失败 pyenv local 设置就成功了 不知道啥原因

dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ pyenv global 3.6.1
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ python -V
Python 2.7.16
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ pyenv global 3.6.1
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ python -V
Python 2.7.16
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ pyenv global 3.6.1
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ python -V
Python 2.7.16
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ sudo pyenv global 3.6.1
[sudo] password for dev:
sudo: pyenv: command not found
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ pyenv -v
pyenv 1.2.9-19-g7d02b246

dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ pyenv global --unset
pyenv: version `--unset' not installed
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ pyenv local 3.6.1
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$ python -V
Python 3.6.1
dev@PC-20190309QPVT:/mnt/c/data/htdocs/python/flaskr$