code: def get_nuclearity_type(child_types):
      
      if 'text' in child_types and len(child_types) == 1:
          return NucType.edu
  
      assert 'nucleus' in child_types, \
          "This is not a relational node. child_types: {}".format(child_types)
  
      if 'satellite' not in child_types:
          assert len(child_types['nucleus']) > 1
          return NucType.multinuc
  
      else:  # 'satellite' in child_types
          assert len(child_types['nucleus']) == 1
          if len(child_types['satellite']) == 1:
              return NucType.nucsat
          else:
              assert len(child_types['satellite']) > 1
              return NucType.multisat
docs: Returns the nuclearity type of an RST relation (i.e. 'multinuc',
      'nucsat' or 'multisat') or 'edu' if the node is below the relation
      level.