new_contents: # Writes all the pdb ids to a txt file so they can be recursively parsed into the pdb_parser
  
  from os import listdir
  from os.path import isfile, join
  
  pdb_list =  listdir('PDB_coordinates')
  
  pdb_id_list = []
  for pdb in pdb_list:
      pdb_id_list.append(pdb[0:4])
  
  for pdb in pdb_id_list:
      print pdb
  
subject: Create pdb_id_writer.py