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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 check_publish_block(self, block_header):
 """Check if a candidate block is ready to be claimed. block_header (BlockHeader):
 the block_header to be checked if it should be claimed Returns: Boolean: True if the candidate block_header should be claimed. """

        if any(publisher_key != block_header.signer_public_key
               for publisher_key in self._valid_block_publishers):
            return False

        if self._min_wait_time == 0:
            return True

        if self._min_wait_time < 0:
            return False

        assert self._min_wait_time > 0

        if self._max_wait_time <= 0:
            return self._start_time + self._min_wait_time <= time.time()

        assert self._max_wait_time > 0

        if self._max_wait_time <= self._min_wait_time:
            return False

        assert 0 < self._min_wait_time < self._max_wait_time

        return self._start_time + self._wait_time <= time.time()