问RuntimeError:即使在pip安装忍者之后，忍者也必须加载C++扩展。

EN

UserWarning: Just-in-time loading and compiling the CUDA kernels of SRU was unsuccessful. Got the following error:
Ninja is required to load C++ extensions
  warnings.warn("Just-in-time loading and compiling the CUDA kernels of SRU was unsuccessful. "
Traceback (most recent call last):
  File "/home/.../.local/lib/python3.8/site-packages/sru/cuda_functional.py", line 15, in <module>
    load(
  File ""/home/.../.local/lib/python3.8/site-packages/torch/utils/cpp_extension.py", line 1080, in load
    return _jit_compile(
  File ""/home/.../.local/lib/python3.8/site-packages/torch/utils/cpp_extension.py", line 1293, in _jit_compile
    _write_ninja_file_and_build_library(
  File ""/home/.../.local/lib/python3.8/site-packages/torch/utils/cpp_extension.py", line 1374, in _write_ninja_file_and_build_library
    verify_ninja_availability()
  File ""/home/.../.local/lib/python3.8/site-packages/torch/utils/cpp_extension.py", line 1430, in verify_ninja_availability
    raise RuntimeError("Ninja is required to load C++ extensions")
RuntimeError: Ninja is required to load C++ extensions

During handling of the above exception, another exception occurred: