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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def gen(self, text, start=0):
 """Return the source code in text, filled with autogenerated code starting at start. """


        for cc in self.chunkComment(text, start):
            c = self.extractChunkContent(cc)
            cc = ''.join(cc)
            m = self.matchComment(c)
            idx = text.index(cc, start)
            e = idx + len(cc)
            if m:
                assert text[idx:e] == cc

                try:
                    end = text.index('\n\n', e - 1) + 1
                except ValueError:
                    end = len(text)
                text = text[:e] + text[end:]
                new = self.genOutputs(self.code(text), m)
                new = ''.join(new)
                text = text[:e] + new + text[e:]

                return self.gen(text, e + len(new))
        return text