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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 _search(self):
 """Returns all documents in the doc dict. This function is not a part of the DocManager API, and is only used to simulate searching all documents from a backend. """

        results = []
        for _id in self.doc_dict:
            entry = self.doc_dict[_id]
            if entry.doc is not None:
                results.append(entry.merged_dict)
        return results