code: def join(l, conj=CONJUNCTION, im_a_moron=MORON_MODE, separator=COMMA):
      
  
      collector = []
      left = len(l)
      separator = separator + SPACE
      conj = conj + SPACE
  
      for _l in l[:]:
  
          left += -1
  
          collector.append(_l)
          if left == 1:
              if len(l) == 2 or im_a_moron:
                  collector.append(SPACE)
              else:
                  collector.append(separator)
  
              collector.append(conj)
  
          elif left is not 0:
              collector.append(separator)
  
      return unicode(str().join(collector))
docs: Joins lists of words. Oxford comma and all.