code: def flatten_sdf_string(sdf_string):
      return sdf_string.replace("\n", ";;;")
  
file_path: PGL/examples/kddcup2021/PCQM4M/features/obabel_utils.py
imports: import os
  from rdkit import Chem
label_desc: Use image node_id 6 for calling a global function with example usage: flatten_sdf_string(sdf_string) and returns: sdf_string