In Python, how can I test if I'm in Google App Engine SDK?

Question

Whilst developing I want to handle some things slight differently than I will when I eventually upload to the Google servers.

Is there a quick test that I can do to

Answer 1

A more general solution
A more general solution, which does not imply to be on a Google server, detects if the code is running on your local machine. I am using the code below regardless the hosting server:

import socket

if socket.gethostname() == "your local computer name":
    DEBUG = True
    ALLOWED_HOSTS = ["127.0.0.1", "localhost", ]
    ...
else:
    DEBUG = False
    ALLOWED_HOSTS = [".your_site.com",]
    ...

If you use macOS you could write a more generic code:

if socket.gethostname().endswith(".local"): # True in your local computer
    ...

Django developers must put this sample code in the file settings.py of the project.

EDIT:
According to Jeff O'Neill in macOS High Sierra socket.gethostname() returns a string ending in ".lan".