升级 Python 包 dateutil:找不到版本

Upgrade the Python package dateutil: Could not find a version

我尝试使用 pip install dateutil --upgradedateutil2.5.3 升级到最新版本 2.6.0,但遇到了问题 Could not find a version

$ pip install dateutil --upgrade
Collecting dateutil
  Could not find a version that satisfies the requirement dateutil (from versions: )
No matching distribution found for dateutil

我检查了 post 。 运行 pip freeze | grep dateutil 得到了,

$ pip freeze | grep dateutil
python-dateutil==2.5.3

我怎么知道哪个版本适合我的机器?是否可以将 dateutil 升级到最新版本?

pip install python-dateutil --upgrade