code: def mark_list(line: str) -> List[int]:
      """
      Given a string, return a list of index positions where a character/non blank space exists.
  
      :param line:
      :return:
  
      >>> mark_list(" a b c")
      [1, 3, 5]
      """
      marks = []
      for idx, car in enumerate(list(line)):
          if car != " ":
              marks.append(idx)
      return marks
  
imports: import re
  import sys
  import unicodedata
  from typing import Dict, List, Tuple
label_desc: Use image node_id 4 for calling a global function with example usage: mark_list(line) and returns: marks