Cannot use Master Key with a logged in user

[cjbland]

I'm developing a very basic administrator portal that needs to update objects that do not belong to them. Because I have a logged in user, the execute method is taking the session token over the Master Key:

https://github.com/milesrichardson/ParsePy/blob/1623d6dd2dc049d978f9cec275e3abcca9dce356/parse_rest/connection.py#L132-L135

Could this be broken into two ifs instead of an if/elif?