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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 insert_many(cls, documents):
 """Insert a list of documents"""

        from mongoframes.queries import to_refs

        # Ensure all documents have been converted to frames
        frames = cls._ensure_frames(documents)

        # Send insert signal
        signal('insert').send(cls, frames=frames)

        # Prepare the documents to be inserted
        documents = [to_refs(f._document) for f in frames]

        # Bulk insert
        ids = cls.get_collection().insert_many(documents).inserted_ids

        # Apply the Ids to the frames
        for i, id in enumerate(ids):
            frames[i]._id = id

        # Send inserted signal
        signal('inserted').send(cls, frames=frames)

        return frames