pyvenv/path/to/new/virtual/environment

c:\Temp>c:\Python35\python c:\Python35\Tools\Scripts\pyvenv.py myenv

c:\Temp>c:\Python35\python -m venv myenv

usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear]            [--upgrade] [--without-pip]            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.optional arguments:  -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)

importosimportos.pathfromsubprocessimportPopen,PIPEimportsysfromthreadingimportThreadfromurllib.parseimporturlparsefromurllib.requestimporturlretrieveimportvenvclassExtendedEnvBuilder(venv.EnvBuilder):"""    This builder installs setuptools and pip so that you can pip or    easy_install other packages into the created environment.    :param nodist: If True, setuptools and pip are not installed into the                   created environment.    :param nopip: If True, pip is not installed into the created                  environment.    :param progress: If setuptools or pip are installed, the progress of the                     installation can be monitored by passing a progress                     callable. If specified, it is called with two                     arguments: a string indicating some progress, and a                     context indicating where the string is coming from.                     The context argument can have one of three values:                     'main', indicating that it is called from virtualize()                     itself, and 'stdout' and 'stderr', which are obtained                     by reading lines from the output streams of a subprocess                     which is used to install the app.                     If a callable is not specified, default progress                     information is output to 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):"""        Set up any packages which need to be pre-installed into the        environment being created.        :param context: The information for the environment creation request                        being processed.        """os.environ['VIRTUAL_ENV']=context.env_dirifnotself.nodist:self.install_setuptools(context)# Can't install pip without setuptoolsifnotself.nopipandnotself.nodist:self.install_pip(context)defreader(self,stream,context):"""        Read lines from a subprocess' output stream and either pass to a progress        callable (if specified) or write progress information to 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)# Download script into the env's binaries folderurlretrieve(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()# Install in the envargs=[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')# Clean up - no longer neededos.unlink(distpath)definstall_setuptools(self,context):"""        Install setuptools in the environment.        :param context: The information for the environment creation request                        being processed.        """url='https://bitbucket.org/pypa/setuptools/downloads/ez_setup.py'self.install_script(context,'setuptools',url)# clear up the setuptools archive which gets downloadedpred=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):"""        Install pip in the environment.        :param context: The information for the environment creation request                        being processed.        """url='https://raw.github.com/pypa/pip/master/contrib/get-pip.py'self.install_script(context,'pip',url)defmain(args=None):compatible=Trueifsys.version_info<(3,3):compatible=Falseelifnothasattr(sys,'base_prefix'):compatible=Falseifnotcompatible:raiseValueError('This script is only for use with ''Python 3.3 or later')else: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 to create the environment in.')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 ''environment directory if it ''already exists, before ''environment creation.')parser.add_argument('--upgrade',default=False,action='store_true',dest='upgrade',help='Upgrade the 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)