[Doc] Add Python docstring for some operators (#2586)
[Doc] Add Python docstring for some operators (#2586)

* Update python/taichi/lang/ops.py

* Update python/taichi/lang/ops.py

Co-authored-by: ljcc0930 <953310eb562334e499fc2456ce61432ad91acebf@qq.com>

Co-authored-by: ljcc0930 <953310eb562334e499fc2456ce61432ad91acebf@qq.com>
Co-authored-by: Ye Kuang <4b45f682edc0f60a7ee973114ff9390ff2416366@users.noreply.github.com>
yuanming-hu/taichi,yuanming-hu/taichi,yuanming-hu/taichi,yuanming-hu/taichi