我是Python的初学者。当我想安装 NumPy 时，我没有工作，特别是当执行到“准备轮元数据”这一行时，出现错误：
C:\Users\dell>pip install numpy
Defaulting to user installation because normal site-packages is not writeable
Collecting numpy
Using cached numpy-1.19.2.zip (7.3 MB)
Installing build dependencies ... done
Getting requirements to build wheel ... done
Preparing wheel metadata ... error
ERROR: Command errored out with exit status 1: 'c:\program files\python39\python.exe' 'c:\program files\python39\lib\site-packages\pip\_vendor\pep517\_in_process.py' prepare_metadata_for_build_wheel 'C:\Users\dell\AppData\Local\Temp\tmphnzlje19' Check the logs for full command output.