code: def get_index_from_first_digit(first_digit: int) -> int:
      number_index = 0
      if first_digit >= 8:  # s have 4 chars
          number_index += 1
  
      first_digit -= 2  # start in 200
  
      number_index += first_digit * 3  # jump 3 every time
  
      return number_index
  
file_path: Ciphey/ciphey/basemods/Decoders/multi_tap.py
imports: from typing import Dict, Optional
  from ciphey.iface import Config, Decoder, ParamSpec, T, U, registry
label_desc: Use image node_id 7 for calling the Multi_tap obj's underlying member method code with example usage: obj.get_index_from_first_digit(first_digit) and returns: number_index