code: def permutationTest2(a, b):
      ab = a + b
      Tobs = sum(a)
      under = 0
      for count, perm in enumerate(comb(ab, len(a)), 1):
          if sum(perm) <= Tobs:
              under += 1
      return under * 100.0 / count
  
imports: from itertools import combinations
label_desc: Use image node_id 3 for calling a global function with example usage: permutationTest2(a, b) and returns: unknown