使用特定版本的python创建虚拟环境

问题描述

我安装了两个版本的python

   Microsoft (R) Build Engine version 15.9.21+g9802d43bc3 for .NET Framework
    copyright (C) Microsoft Corporation. All rights reserved.

    C:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\Common7\IDE\VC\VCTargets\Microsoft.CppBuild.targets(399,5): warning MSB8029: The Intermediate directory or Output directory cannot reside under the Temporary directory as it Could lead to issues with incremental build. [C:\Users\Paul\AppData\Local\Temp\pip-install-xvvf77_z\llvmlite\ffi\build\ZERO_CHECK.vcxproj]
    C:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\Common7\IDE\VC\VCTargets\Microsoft.CppBuild.targets(399,5): warning MSB8029: The Intermediate directory or Output directory cannot reside under the Temporary directory as it Could lead to issues with incremental build. [C:\Users\Paul\AppData\Local\Temp\pip-install-xvvf77_z\llvmlite\ffi\build\llvmlite.vcxproj]
    LINK : Fatal error LNK1181: cannot open input file 'D:\winlibs64_stage\custombuilt\lib\libffi.dll.a' [C:\Users\Paul\AppData\Local\Temp\pip-install-xvvf77_z\llvmlite\ffi\build\llvmlite.vcxproj]
    Trying generator 'Visual Studio 15 2017 Win64'
    Traceback (most recent call last):
      File "C:\Users\Paul\AppData\Local\Temp\pip-install-xvvf77_z\llvmlite\ffi\build.py",line 191,in <module>
        main()
      File "C:\Users\Paul\AppData\Local\Temp\pip-install-xvvf77_z\llvmlite\ffi\build.py",line 179,in main
        main_win32()
      File "C:\Users\Paul\AppData\Local\Temp\pip-install-xvvf77_z\llvmlite\ffi\build.py",line 94,in main_win32
        subprocess.check_call(['cmake','--build',build_dir,'--config',config])
      File "c:\users\paul\appdata\local\programs\python\python39\lib\subprocess.py",line 373,in check_call
        raise CalledProcessError(retcode,cmd)
    subprocess.CalledProcessError: Command '['cmake','C:\\Users\\Paul\\AppData\\Local\\Temp\\pip-install-xvvf77_z\\llvmlite\\ffi\\build','Release']' returned non-zero exit status 1.
    error: command 'c:\\users\\paul\\appdata\\local\\programs\\python\\python39\\python.exe' Failed with exit code 1
    ----------------------------------------
ERROR: Command errored out with exit status 1: 'c:\users\paul\appdata\local\programs\python\python39\python.exe' -u -c 'import sys,setuptools,tokenize; sys.argv[0] = '"'"'C:\\Users\\Paul\\AppData\\Local\\Temp\\pip-install-xvvf77_z\\llvmlite\\setup.py'"'"'; __file__='"'"'C:\\Users\\Paul\\AppData\\Local\\Temp\\pip-install-xvvf77_z\\llvmlite\\setup.py'"'"';f=getattr(tokenize,'"'"'open'"'"',open)(__file__);code=f.read().replace('"'"'\r\n'"'"','"'"'\n'"'"');f.close();exec(compile(code,__file__,'"'"'exec'"'"'))' install --record 'C:\Users\Paul\AppData\Local\Temp\pip-record-l4absc_g\install-record.txt' --single-version-externally-managed --compile --install-headers 'c:\users\paul\appdata\local\programs\python\python39\Include\llvmlite' Check the logs for full command output.

我可以使用第一个版本创建虚拟环境

C:\>python --version
Python 3.6.4

C:\>python39 --version
Python 3.9.0

但是我不能使用3.9版本：

C:\temp_folder>python -m venv env1

创建了env2文件夹，但缺少大多数脚本文件

解决方法

应为python3.9 -m venv env2