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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 get_current(self):
 """ Parse the lease file and return a dict of active and valid Lease instances. The key for this dict is the ethernet address of the lease. """

        all_leases = self.get()
        leases = {}
        for lease in all_leases:
            if lease.valid and lease.active:
                if type(lease) is Lease:
                    leases[lease.ethernet] = lease
                elif type(lease) is Lease6:
                    leases['%s-%s' % (lease.type, lease.host_identifier_string)] = lease
        return leases