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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 delete_many(cls, documents):
 """Delete multiple documents"""


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

        all_count = len(documents)
        assert len([f for f in frames if '_id' in f._document]) == all_count, \
                "Can't delete documents without `_id`s"

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

        # Prepare the documents to be deleted
        ids = [f._id for f in frames]

        # Delete the documents
        cls.get_collection().delete_many({'_id': {'$in': ids}})

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