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### Contributors

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### ENH

- The new IndelMap class uses numpy arrays to store information about gap
  locations for aligned sequences. This will greatly reduce the memory
  overhead for aligned sequences. The class also provides explicit methods
  for inter-converting between sequence and alignment coordinates. An important
  difference to the original Map implementation is that IndelMap is memoryless,
  meaning the history of slice operations is now fully delegated to the SeqView
  class.
- The new FeatureMap class is a slightly modified version of the original Map
  class. It is used solely for handling sequence feature mappings to sequences
  and alignments. Like IndelMap, it is memoryless but it does record its
  orientation with respect to the parent sequence.
- Note that both IndelMap and FeatureMap replace the spans attribute with a
  generator.

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### Discontinued

- The cogent3.core.location.Map class is now marked for deprecation. It is
  being replaced by two classes, IndelMap and FeatureMap. The latter has
  largely the same functionality of Map.


