49   def __eq__(self, other):  argument
50     return self.data == other.data
52   def __ne__(self, other):  argument
53     return self.data != other.data
159   def union(self, other):  argument
171                             zip(other.data, itertools.cycle((+1, -1)))):
177   def intersect(self, other):  argument
189                             zip(other.data, itertools.cycle((+1, -1)))):
195   def subtract(self, other):  argument
208                             zip(other.data, itertools.cycle((-1, +1)))):
214   def overlaps(self, other):  argument
228                             zip(other.data, itertools.cycle((+1, -1)))):
250   def map_within(self, other):  argument
269                             zip(other.data, itertools.cycle((-1, +1)))):