code: def create_system(numbering_type=NUMBERING_TYPES[1]):
      """
      根据数字系统类型返回创建相应的数字系统，默认为 mid
      NUMBERING_TYPES = ['low', 'mid', 'high']: 中文数字系统类型
          low:  '兆' = '亿' * '十' = $10^{9}$,  '京' = '兆' * '十', etc.
          mid:  '兆' = '亿' * '万' = $10^{12}$, '京' = '兆' * '万', etc.
          high: '兆' = '亿' * '亿' = $10^{16}$, '京' = '兆' * '兆', etc.
      返回对应的数字系统
      """
  
      # chinese number units of '亿' and larger
      all_larger_units = zip(
          LARGER_CHINESE_NUMERING_UNITS_SIMPLIFIED,
          LARGER_CHINESE_NUMERING_UNITS_TRADITIONAL,
      )
      larger_units = [
          CNU.create(i, v, numbering_type, False)
          for i, v in enumerate(all_larger_units)
      ]
      # chinese number units of '十, 百, 千, 万'
      all_smaller_units = zip(
          SMALLER_CHINESE_NUMERING_UNITS_SIMPLIFIED,
          SMALLER_CHINESE_NUMERING_UNITS_TRADITIONAL,
      )
      smaller_units = [
          CNU.create(i, v, small_unit=True)
          for i, v in enumerate(all_smaller_units)
      ]
      # digis
      chinese_digis = zip(
          CHINESE_DIGIS,
          CHINESE_DIGIS,
          BIG_CHINESE_DIGIS_SIMPLIFIED,
          BIG_CHINESE_DIGIS_TRADITIONAL,
      )
      digits = [CND.create(i, v) for i, v in enumerate(chinese_digis)]
      digits[0].alt_s, digits[0].alt_t = ZERO_ALT, ZERO_ALT
      digits[1].alt_s, digits[1].alt_t = ONE_ALT, ONE_ALT
      digits[2].alt_s, digits[2].alt_t = TWO_ALTS[0], TWO_ALTS[1]
  
      # symbols
      positive_cn = CM(POSITIVE[0], POSITIVE[1], "+", lambda x: x)
      negative_cn = CM(NEGATIVE[0], NEGATIVE[1], "-", lambda x: -x)
      point_cn = CM(
          POINT[0],
          POINT[1],
          ".",
          lambda x, y: float(str(x) + "." + str(y)),
      )
      # sil_cn = CM(SIL[0], SIL[1], '-', lambda x, y: float(str(x) + '-' + str(y)))
      system = NumberSystem()
      system.units = smaller_units + larger_units
      system.digits = digits
      system.math = MathSymbol(positive_cn, negative_cn, point_cn)
      # system.symbols = OtherSymbol(sil_cn)
      return system
  
imports: import argparse
  import codecs
  import os
  import re
  import string
  import sys
label_desc: Use image node_id 1 for calling a global function with example usage: create_system(numbering_type) and returns: system