def METHOD_NAME(self, brids, claimed_at=None):
    for brid in brids:
        if brid not in self.reqs or brid in self.claims:
            raise buildrequests.AlreadyClaimedError
    if claimed_at is not None:
        claimed_at = datetime2epoch(claimed_at)
    else:
        claimed_at = int(self.reactor.seconds())
    # now that we've thrown any necessary exceptions, get started
    for brid in brids:
        self.claims[brid] = BuildRequestClaim(brid=brid,
                                              masterid=self.MASTER_ID,
                                              claimed_at=claimed_at)
    return defer.succeed(None)