                          UNIT: [],
                          OUT: ['']
                      })
          for entity_type in kwargs.get('entity_types', []):
              if entity_type in seen_entities:
                  continue
              seen_entities.add(entity_type)
              for action in (BEGIN, IN, LAST, UNIT):
 
</s> remove                         MISSING: {'': True},
                        BEGIN: {},
                        IN: {},
                        LAST: {},
                        UNIT: {},
                        OUT: {'': True}
 </s> add                         MISSING: [''],
                        BEGIN: [],
                        IN: [],
                        LAST: [],
                        UNIT: [],
                        OUT: [''] </s> remove                 actions[action][entity_type] = True
 </s> add                 actions[action].append(entity_type) </s> remove                         for move_str in ('B', 'I', 'L', 'U'):
                            actions[moves.index(move_str)][label] = True
 </s> add                         if label not in seen_entities:
                            seen_entities.add(label)
                            for move_str in ('B', 'I', 'L', 'U'):
                                actions[moves.index(move_str)].append(label) </s> remove                         SHIFT: {'': True},
                        REDUCE: {'': True},
                        RIGHT: {},
                        LEFT: {},
                        BREAK: {'ROOT': True}})
 </s> add                         SHIFT: [''],
                        REDUCE: [''],
                        RIGHT: [],
                        LEFT: [],
                        BREAK: ['ROOT']})
        seen_actions = set()
        seen_entities = set()
                          UNIT: [],
                          OUT: ['']
                      })
        seen_entities = set()
          for entity_type in kwargs.get('entity_types', []):
              if entity_type in seen_entities:
                  continue
              seen_entities.add(entity_type)
              for action in (BEGIN, IN, LAST, UNIT):
keep keep add keep keep keep keep keep
 WIP on add_label bug during NER training

Currently when a new label is introduced to NER during training,
it causes the labels to be read in in an unexpected order. This
invalidates the model. 
spacy/syntax/ner.pyx