code: def insert_many(cls, 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
docs: Insert a list of documents