taichi: I can't install taichi by pip

Describe the bug I can’t install taichi by pip

Log/Screenshots

C:\Users\work>pip install taichi-nightly
ERROR: Could not find a version that satisfies the requirement taichi-nightly (from versions: none)
ERROR: No matching distribution found for taichi-nightly

C:\Users\work>pip3 install -i https://pypi.org/project/ taichi-nightly
Looking in indexes: https://pypi.org/project/
ERROR: Could not find a version that satisfies the requirement taichi-nightly (from versions: none)
ERROR: No matching distribution found for taichi-nightly

C:\Users\work>pip3 install -i https://pypi.org/project/ taichi-nightly==0.3.9
Looking in indexes: https://pypi.org/project/
ERROR: Could not find a version that satisfies the requirement taichi-nightly==0.3.9 (from versions: none)
ERROR: No matching distribution found for taichi-nightly==0.3.9

C:\Users\work>pip install -i https://pypi.tuna.tsinghua.edu.cn/simple taichi-nightly
Looking in indexes: https://pypi.tuna.tsinghua.edu.cn/simple
ERROR: Could not find a version that satisfies the requirement taichi-nightly (from versions: none)
ERROR: No matching distribution found for taichi-nightly

C:\Users\work>pip install -i https://pypi.tuna.tsinghua.edu.cn/simple taichi-nightly==0.3.9
Looking in indexes: https://pypi.tuna.tsinghua.edu.cn/simple
ERROR: Could not find a version that satisfies the requirement taichi-nightly==0.3.9 (from versions: none)
ERROR: No matching distribution found for taichi-nightly==0.3.9