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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 eth_getBlockByNumber(self, number):
 """Get block body by block number. :param number: :return: """

        block_hash = self.reader._get_block_hash(number)
        block_number = _format_block_number(number)
        body_key = body_prefix + block_number + block_hash
        block_data = self.db.get(body_key)
        body = rlp.decode(block_data, sedes=Block)
        return body