The disadvantage of sre_deprecate_pattern_keyword-3.4.patch is that it creates 
false signature for SRE_Pattern.match(). Default value of first argument is 
exposed as None, but actually this parameter is mandatory and None is not 
valid value for it. I afraid the only way to get rid of false signature (and 
keep backward compatibility) is to revert converting to Argument Clinic.  And 
here is a patch which do this.