Question about getting an IP address in Genie

I am a novice in Django and I got this code from a specialist, but I do not know how it works and how anyone can explain how it works?

def get_client_ip(request):
    x_forwarded_for = request.META.get('HTTP_X_FORWARDED_FOR')
    if x_forwarded_for:
        ip = x_forwarded_for.split(',')[0]
    else:
        ip = request.META.get('REMOTE_ADDR')
    return ip