New in version 1.1.
Partition sequence elements once by weights exactly without overhang:
abjad> from abjad.tools import sequencetools
abjad> sequence = [3, 3, 3, 3, 4, 4, 4, 4, 5, 5]
abjad> sequencetools.partition_sequence_once_by_weights_exactly_without_overhang(sequence, [3, 9])
[[3], [3, 3, 3]]
Return list sequence element reference lists.
Changed in version 2.0: renamed sequencetools.group_sequence_elements_once_by_weights_exactly_without_overhang() to sequencetools.partition_sequence_once_by_weights_exactly_without_overhang().