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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 mine_block(chain: MiningChain, **kwargs: Any) -> MiningChain: """ Mine a new block on the chain. Header parameters for the new block can be overridden using keyword arguments. """

    if not isinstance(chain, MiningChain):
        raise ValidationError('`mine_block` may only be used on MiningChain instances')
    chain.mine_block(**kwargs)
    return chain