Pretty cool! However, some riddles are incorrect, for example this one has two errors:

  def foo( vals ):
    output = vals[0]
    for x in vals[1:]:
      if output < x:
        output = x
    return x

1. It should return output

2. The answer should be "The maximum value", not "The minimum value"

Also, it could be nice if after you solve a riddle you would get a new one.