def postings(self, fieldid, text, exclude_docs = None):
        format = self.schema[fieldid].format
        postreaders = []
        docoffsets = []
        for i, r in enumerate(self.readers):
            if (fieldid, text) in r:
                postreaders.append(r.postings(fieldid, text, exclude_docs=exclude_docs))
                docoffsets.append(self.doc_offsets[i])
        if not postreaders:
            raise TermNotFound(fieldid, text)
        else:
            return MultiPostingReader(format, postreaders, docoffsets)
dataset/ETHPy150Open dokipen/whoosh/src/whoosh/reading.py/MultiReader.postings/original