code: def check_valid(number, input_base=10):
      
      for n in number:
          if n in (".", "[", "]"):
              continue
          elif n >= input_base:
              if n == 1 and input_base == 1:
                  continue
              else:
                  return False
      return True
docs: Checks if there is an invalid digit in the input number.
  
      Args:
          number: An number in the following form:
              (int, int, int, ... , '.' , int, int, int)
              (iterable container) containing positive integers of the input base
          input_base(int): The base of the input number.
  
      Returns:
          bool, True if all digits valid, else False.
  
      Examples:
          >>> check_valid((1,9,6,'.',5,1,6), 12)
          True
          >>> check_valid((8,1,15,9), 15)
          False