'Collects any information that\'s necessary to execute this
transformer\'s transform method.'

@classmethod
def collect(cls, block_structure):

    collect_merged_boolean_field(block_structure, transformer=cls, xblock_field_name='hide_after_due', merged_field_name=cls.MERGED_HIDE_AFTER_DUE)
    collect_merged_date_field(block_structure, transformer=cls, xblock_field_name='due', merged_field_name=cls.MERGED_DUE_DATE, default_date=MAXIMUM_DATE, func_merge_parents=max, func_merge_ancestors=min)
    block_structure.request_xblock_fields(u'self_paced', u'end')
