python-mvenv/path/to/new/virtual/environment

PS>python-mvenvC:\path\to\new\virtual\environment

usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear]            [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps]            [--without-scm-ignore-files]            ENV_DIR [ENV_DIR ...]Creates virtual Python environments in one or more target directories.positional arguments:  ENV_DIR               A directory to create the environment in.options:  -h, --help            show this help message and exit  --system-site-packages                        Give the virtual environment access to the system                        site-packages dir.  --symlinks            Try to use symlinks rather than copies, when                        symlinks are not the default for the platform.  --copies              Try to use copies rather than symlinks, even when                        symlinks are the default for the platform.  --clear               Delete the contents of the environment directory                        if it already exists, before environment creation.  --upgrade             Upgrade the environment directory to use this                        version of Python, assuming Python has been                        upgraded in-place.  --without-pip         Skips installing or upgrading pip in the virtual                        environment (pip is bootstrapped by default)  --prompt PROMPT       Provides an alternative prompt prefix for this                        environment.  --upgrade-deps        Upgrade core dependencies (pip) to the latest                        version in PyPI  --without-scm-ignore-files                        Skips adding SCM ignore files to the environment                        directory (Git is supported by default).Once an environment has been created, you may wish to activate it, e.g. bysourcing an activate script in its bin directory.

importosimportos.pathfromsubprocessimportPopen,PIPEimportsysfromthreadingimportThreadfromurllib.parseimporturlparsefromurllib.requestimporturlretrieveimportvenvclassExtendedEnvBuilder(venv.EnvBuilder):"""    此建構子會安裝 setuptools 和 pip，使你能夠使用 pip 或    easy_install 安裝其他套件到建立的虛擬環境中。    :param nodist: 若為 true，則不會安裝 setuptools 和 pip 至                   所建立的虛擬環境中。    :param nopip: 若為 true，則不會安裝 pip 至所建立的                  虛擬環境中。    :param progress: 若安裝了 setuptools 或 pip，可透過傳入 progress                     可呼叫物件來監控安裝進度。若有指定，該可呼叫物件會接收兩個引數：                     一個表示進度的字串，以及一個表示該字串來源的情境。                     context 引數可能有三種值：                     'main' 表示該呼叫來自 virtualize() 本身，                     'stdout' 與 'stderr' 則分別表示從子行程輸出資料串流中                     讀取的輸出內容，該子行程用於安裝應用程式。                     若未指定可呼叫物件，則預設的進度資訊會輸出至 sys.stderr。    """def__init__(self,*args,**kwargs):self.nodist=kwargs.pop('nodist',False)self.nopip=kwargs.pop('nopip',False)self.progress=kwargs.pop('progress',None)self.verbose=kwargs.pop('verbose',False)super().__init__(*args,**kwargs)defpost_setup(self,context):"""        設定在建立虛擬環境時需預先安裝的套件。        :param context: 處理中的虛擬環境建立請求所需的資訊。        """os.environ['VIRTUAL_ENV']=context.env_dirifnotself.nodist:self.install_setuptools(context)# 沒有 setuptools 就無法安裝 pipifnotself.nopipandnotself.nodist:self.install_pip(context)defreader(self,stream,context):"""        從子行程的輸出串流中讀取每一列，並將其傳遞給進度回呼函式（若有指定），或將進度資訊寫入 sys.stderr。        """progress=self.progresswhileTrue:s=stream.readline()ifnots:breakifprogressisnotNone:progress(s,context)else:ifnotself.verbose:sys.stderr.write('.')else:sys.stderr.write(s.decode('utf-8'))sys.stderr.flush()stream.close()definstall_script(self,context,name,url):_,_,path,_,_,_=urlparse(url)fn=os.path.split(path)[-1]binpath=context.bin_pathdistpath=os.path.join(binpath,fn)# 將腳本下載到虛擬環境的執行檔資料夾中urlretrieve(url,distpath)progress=self.progressifself.verbose:term='\n'else:term=''ifprogressisnotNone:progress('Installing%s ...%s'%(name,term),'main')else:sys.stderr.write('Installing%s ...%s'%(name,term))sys.stderr.flush()# 安裝到虛擬環境中args=[context.env_exe,fn]p=Popen(args,stdout=PIPE,stderr=PIPE,cwd=binpath)t1=Thread(target=self.reader,args=(p.stdout,'stdout'))t1.start()t2=Thread(target=self.reader,args=(p.stderr,'stderr'))t2.start()p.wait()t1.join()t2.join()ifprogressisnotNone:progress('done.','main')else:sys.stderr.write('done.\n')# 清理——不再需要os.unlink(distpath)definstall_setuptools(self,context):"""        Install setuptools in the virtual environment.        :param context: The information for the virtual environment                        creation request being processed.        """url="https://bootstrap.pypa.io/ez_setup.py"self.install_script(context,'setuptools',url)# 清除已下載的 setuptools 檔案pred=lambdao:o.startswith('setuptools-')ando.endswith('.tar.gz')files=filter(pred,os.listdir(context.bin_path))forfinfiles:f=os.path.join(context.bin_path,f)os.unlink(f)definstall_pip(self,context):"""        在虛擬環境中安裝 pip。        :param context: 處理中的虛擬環境建立請求相關資訊。        """url='https://bootstrap.pypa.io/get-pip.py'self.install_script(context,'pip',url)defmain(args=None):importargparseparser=argparse.ArgumentParser(prog=__name__,description='Creates virtual Python ''environments in one or ''more target ''directories.')parser.add_argument('dirs',metavar='ENV_DIR',nargs='+',help='A directory in which to create the ''virtual environment.')parser.add_argument('--no-setuptools',default=False,action='store_true',dest='nodist',help="Don't install setuptools or pip in the ""virtual environment.")parser.add_argument('--no-pip',default=False,action='store_true',dest='nopip',help="Don't install pip in the virtual ""environment.")parser.add_argument('--system-site-packages',default=False,action='store_true',dest='system_site',help='Give the virtual environment access to the ''system site-packages dir.')ifos.name=='nt':use_symlinks=Falseelse:use_symlinks=Trueparser.add_argument('--symlinks',default=use_symlinks,action='store_true',dest='symlinks',help='Try to use symlinks rather than copies, ''when symlinks are not the default for ''the platform.')parser.add_argument('--clear',default=False,action='store_true',dest='clear',help='Delete the contents of the ''virtual environment ''directory if it already ''exists, before virtual ''environment creation.')parser.add_argument('--upgrade',default=False,action='store_true',dest='upgrade',help='Upgrade the virtual ''environment directory to ''use this version of ''Python, assuming Python ''has been upgraded ''in-place.')parser.add_argument('--verbose',default=False,action='store_true',dest='verbose',help='Display the output ''from the scripts which ''install setuptools and pip.')options=parser.parse_args(args)ifoptions.upgradeandoptions.clear:raiseValueError('you cannot supply --upgrade and --clear together.')builder=ExtendedEnvBuilder(system_site_packages=options.system_site,clear=options.clear,symlinks=options.symlinks,upgrade=options.upgrade,nodist=options.nodist,nopip=options.nopip,verbose=options.verbose)fordinoptions.dirs:builder.create(d)if__name__=='__main__':rc=1try:main()rc=0exceptExceptionase:print('Error:%s'%e,file=sys.stderr)sys.exit(rc)