DelayedClaimable
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Extension for the Claimable contract, where the ownership needs to be claimed before/after a certain block number.

setLimits(uint256 _start, uint256 _end) onlyOwner
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Specifies the time period during which a pending owner can claim ownership.


claimOwnership( ) onlyPendingOwner
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Completes transfer of ownership by setting pending owner as the new owner.