def holes(self):
        '''Return holes in collection.

        Return :py:class:`~clique.collection.Collection` of missing indexes.

        '''
        missing = set([])
        previous = None
        for index in self.indexes:
            if previous is None:
                previous = index
                continue

            if index != (previous + 1):
                missing.update(range(previous + 1, index))

            previous = index

        return Collection(self.head, self.tail, self.padding, indexes=missing)
def holes ( self ) : missing = set ( [ ] ) previous = None for index in self . indexes : if previous is None : previous = index continue if index != ( previous + 1 ) : missing . update ( range ( previous + 1 , index ) ) previous = index return Collection ( self . head , self . tail , self . padding , indexes = missing )
Return holes in collection.

        Return :py:class:`~clique.collection.Collection` of missing indexes.