Power set

# Number of Combinations = 2**(length of input set)
# Makes use of binary
def PowerSet(input):
  ans = []
  numOfComb = 2 ** len(input)
  for combidx in range(numOfComb): # 0 -> numOfComb
    temp = []
    for setidx in range(len(input)): # 0 -> len(input)
      if combidx & 1 << setidx: # bitwise operation e.g. 0 & 1 << 0 =>0
        temp.append(input[setidx])
      ans.append(temp)
   return ans