parameters: (minuend, subtrahend)
return_statement: return itertools.filterfalse(set(subtrahend).__contains__, minuend)
docstring: Return items in minuend not in subtrahend, retaining order
      with O(1) lookup.
docstring_summary: Return items in minuend not in subtrahend, retaining order
      with O(1) lookup.
docstring_tokens: Return items in minuend not in subtrahend retaining order with O ( 1 ) lookup .
function: def _difference(minuend, subtrahend):
      """
      Return items in minuend not in subtrahend, retaining order
      with O(1) lookup.
      """
      return itertools.filterfalse(set(subtrahend).__contains__, minuend)
function_tokens: def _difference ( minuend , subtrahend ) : return itertools . filterfalse ( set ( subtrahend ) . __contains__ , minuend )