code: def merge(self, collection):
          '''Merge *collection* into this collection.
  
          If the *collection* is compatible with this collection then update
          indexes with all indexes in *collection*.
  
          raise :py:class:`~clique.error.CollectionError` if *collection* is not
          compatible with this collection.
  
          '''
          if not self.is_compatible(collection):
              raise clique.error.CollectionError('Collection is not compatible '
                                                 'with this collection.')
  
          self.indexes.update(collection.indexesf merge(self, collection):
          '''Merge *collection* into this collection.
  
          If the *collection* is compatible with this collection then update
          indexes with all indexes in *collection*.
  
          raise :py:class:`~clique.error.CollectionError` if *collection* is not
          compatible with this collection.
  
          '''
          if not self.is_compatible(collection):
              raise clique.error.CollectionError('Collection is not compatible '
                                                 'with this collection.')
  
          self.indexes.update(collection.indexes)
docs: Merge *collection* into this collection.
  
          If the *collection* is compatible with this collection then update
          indexes with all indexes in *collection*.
  
          raise :py:class:`~clique.error.CollectionError` if *collection* is not
          compatible with this collection.