code: def get_not_num(self, seq, num=0):
          '''Find the index of first non num element'''
          ind = next((i for i, x in enumerate(seq) if x != num), None)
          if ind == None:
              return self.board_size
          else:
              return inf get_not_num(self, seq, num=0):
          '''Find the index of first non num element'''
          ind = next((i for i, x in enumerate(seq) if x != num), None)
          if ind == None:
              return self.board_size
          else:
              return ind
docs: Find the index of first non num element