Sorry for not adding the input/output. Will check for those

Nothing broken (note at the top of the page how many people passed the Python kata). N S W E return [].

Python test cases are broken. N S W E should return [] as you're ending up in the place where you started.

Sorry but nothing broken. Look at the top of the page to see how many guys passed the Python kata (5474). Moreover when you post an issue give a proof by posting the input, your output, the expected result. Cheers.

Python solutions are broken, in some cases it says that the solution should be longer than the input list!

  def diamond(m):
      if m % 2 == 1 and m > 0:
          n = (m - 1) / 2
          s = []
          for i in xrange(n, -1, -1):
              s += [i * ' ', '*' * (m - 2 * i), '\n']
          for i in xrange(1, n+1):
              s += [i * ' ', '*' * (m - 2 * i), '\n']
          return ''.join(s)
      else:
          return None

Indeed. However, the description reads

The length will be 0 < string < 100.

It returns False if you input "", which intuitively seems wrong because all count to zero.