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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 _remove_batches(self, block, keep_batches):
 """Returns a copy of the block without the non-injected batches, which other validators are likely to already have. This reduces the size of the broadcasted block. """

        clone = Block()
        clone.header = block.header
        clone.header_signature = block.header_signature
        clone.batches.extend([
            batch for batch in block.batches
            if batch.header_signature in keep_batches
        ])
        return clone