Custom prompt of PowerShell (posh-git, Python virtualenv)

profile.ps1

### Custom prompt  ###
Import-Module posh-git

# disable default python virtualenv prompt
$env:VIRTUAL_ENV_DISABLE_PROMPT = "1" 

# store the original prompt function
function _prompt {
    ""
}
$function:_prompt = $function:prompt

# get python virtualenv name
function _py_virtual_env {
    $venv = ""
    if ($env:VIRTUAL_ENV) {
        $venv = "$( Split-Path $env:VIRTUAL_ENV -Leaf )"
    }
    $venv
}

# make custom prompt prefix
function _prompt_prefix {
    $prefix = "┌▫"
    $venv = $(_py_virtual_env)
    if ($venv) {
        $prefix += " ($venv)"
    }

    $info = '$(Get-PromptConnectionInfo -Format "[{1}@{0}]: ")'
    ("$prefix $info")
}

# make custom prompt suffix
function _prompt_suffix {
    "`n└$(">" * ($nestedPromptLevel + 1)) "
}

# set the custom prompt
function prompt {
    $GitPromptSettings.DefaultPromptPrefix.Text = $(_prompt_prefix)
    $GitPromptSettings.DefaultPromptSuffix.Text = $(_prompt_suffix)
    Invoke-Command (Get-Item function:_prompt).ScriptBlock
}