Webapp2 Routing and Python inclusion
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It defines a raw string. Please read docs docs.python.org/2/reference/lexical_analysis.html#literals paying special attention to raw strings. You may use a raw string to more easily define a regular expression as a literal string.
In the webapp2 URI routing there are some examples using webapp2.Route(r'/', handler='...'), and some aren't using r'/' -- so my question is, what is the R for, and should I be using it? 
Also, if you use webapp2_extras.APIs you need to pass the config to the WSGIApplication(), is it possible to define the config lists elsewhere?
As in, is it possible to do config['webapp2_extras.API'] = ['option':'value'] in one file, then include that file inside your "router" and use the variable/list
Thanks in advance!!