parameters: (a, b)
return_statement: return Fraction(a.numerator * b.denominator -
                          b.numerator * a.denominator,
                          a.denominator * b.denominator)
docstring: a - b
docstring_summary: a - b
docstring_tokens: a - b
function: def _sub(a, b):
          """a - b"""
          return Fraction(a.numerator * b.denominator -
                          b.numerator * a.denominator,
                          a.denominator * b.denominator)
function_tokens: def _sub ( a , b ) : return Fraction ( a . numerator * b . denominator - b . numerator * a . denominator , a . denominator * b . denominator )