New in version 2.0.
Repeat sequence elements at indices to total length:
abjad> from abjad.tools import sequencetools
abjad> sequencetools.repeat_sequence_elements_at_indices(range(10), [6, 7, 8], 3)
[0, 1, 2, 3, 4, 5, [6, 6, 6], [7, 7, 7], [8, 8, 8], 9]
Return list.