How to create an auth token in a webapp2 script? - python-2.7

Question

I want to make testing endpoints in a Google App Engine instance easier by using a script. Based on this information https://webapp-improved.appspot.com/guide/testing.html, I wrote a simple script like this:
from main import app
params = {
'top': 'true',
'sort_by': 'most-recent',
}
query = urllib.urlencode(params)
url = '/activities?' + query
request = webapp2.Request.blank(url)
response = request.get_response(app)
But there is a problem: my handler has a security check to ensure only signed-in user can call the endpoint. It will return status code of 401 (HTTPUnauthorized) if the cookie __auth__ is not set propertly
HTTPUnauthorized: This server could not verify that you are authorized to access the document you requested. Either you supplied the wrong credentials (e.g., bad password), or your browser does not understand how to supply the credentials required.
Here is the relevant webapp2 configuration
'webapp2_extras.sessions': {
'cookie_name': '__session__',
'secret_key': login.secrets.SESSION_KEY,
'cookie_args': {
'max_age': 30 * 24 * 60 * 60
}
},
'webapp2_extras.auth': {
'cookie_name': '__auth__',
# Use with 'remember' flag to make persistent cookies
'token_max_age': 30 * 24 * 60 * 60,
'user_attributes': []
},
I have tried to 'monkey-patch' my handler classes to bypass the check.
Here is the get function of my handler class ActivitiesHandler (it extends webapp2.RequestHandler)
def get(self):
# Checking if user is logged in
if self.secure and not self.logged_in:
self.abort(401)
# ...
My money patch code goes like this:
ActivitiesHandler.secure = False
However it does not take any effect. I think it is because the app variable, being a variable of a module scope, is already initialised along with all the handlers well before my money patch code is executed.
As an alternative, I want to programmatically create a __auth__ for a valid User entity. But I cannot find relevant information regarding this.
Any pointer or sample code will be welcome.