# Set virtual environment (windows 10 system)
method1: virtualenv  virtualenv_eslearn
method2: mkvirtualenv virtualenv_eslearn
method3: virtualenv -p F:\Python3.6.5_V2\python.exe virtualenv_eslearn

# Check current environment (PowerShell)
$old_path = [environment]::GetEnvironmentvariable("Path", "User")

# Add new_added_path to environment PATH (PowerShell)
$old_path = [environment]::GetEnvironmentvariable("PATH", "User")
$new_added_path = 'YourPath'
$new_path = $old_path, $new_added_path -Join ";"
[environment]::SetEnvironmentvariable("PATH", $new_path, "User")