docs: def start(st_reg_number):
      """Checks the number valiaty for the Pernanbuco state"""
      divisor = 11
  
      if len(st_reg_number) > 9:
          return False
  
      if len(st_reg_number) < 9:
          return False
  
      sum_total = 0
      peso = 8
      for i in range(len(st_reg_number)-2):
          sum_total = sum_total + int(st_reg_number[i]) * peso
          peso = peso - 1
  
          rest_division = sum_total % divisor
          digit_first = divisor - rest_division
  
      if rest_division < 2:
          digit_first = 0
  
      if rest_division > 1:
          digit_first = 11 - rest_division
  
      num = 0
      peso = 9
      mult = 10000000
      for i in range(len(st_reg_number)-2):
          num = num + int(st_reg_number[i]) * mult
          mult = mult/10
  
      num = num + digit_first
  
      new_st = str(num)
      sum_total = 0
      peso = 9
      for i in range(len(new_st)-1):
          sum_total = sum_total + int(new_st[i]) * peso
          peso = peso - 1
  
      rest_division = sum_total % divisor
  
      if rest_division < 2:
          digit_secund = 0
  
      if rest_division > 1:
          digit_secund = divisor - rest_division
  
      if digit_secund == int(st_reg_number[len(st_reg_number)-1]) and digit_first == int(st_reg_number[len(st_reg_number)-2]):
          return True
      else:
          return False