def _compile(self, expression):
        """
        Transform a class exp into an actual regex
        """

        x = self.RE_PYTHON_VAR.sub('(?:\\1,)', expression)
        x = self.RE_SPACES.sub('', x)
        return re.compile(x)
def _compile ( self , expression ) : x = self . RE_PYTHON_VAR . sub ( '(?:\\1,)' , expression ) x = self . RE_SPACES . sub ( '' , x ) return re . compile ( x )
Transform a class exp into an actual regex