text: from itertools import combinations
  
  def solution(number, k):
      answer = ''
      max = -1
      l = list(combinations(str([x for x in range(len(number))]),k))
      for ml in l:
          temp = number
          for i in range(len(ml)):
              del temp[ml[i-1] - i]
          t = int(''.join(temp))
          if max < t:
              max = t
      answer = str(max)
      return answer
  