code: def flatten_unique(l):
      l_flat = []
      for l_i in l:
          for l_ij in l_i:
              l_flat.append(l_ij)
      return list(set(l_flat))
  
imports: import pickle
  from itertools import chain, combinations
label_desc: Use image node_id 3 for calling a global function with example usage: flatten_unique(l) and returns: list