old_contents: import glob
  
  fout=open("out.csv","a")
  # first file:
  fout.write("clip,seizure,early\n")
  
  files_list = glob.glob('*.csv')
  
  for file_item in files_list:
      f = open(file_item)
      f.next() # skip the header
      for line in f:
           fout.write(line)
      f.close() 
  fout.close()
  
new_contents: import glob
  
  output_fname = "out.csv"
  fout=open(output_fname,"a")
  # first file:
  fout.write("clip,seizure,early\n")
  
  files_list = glob.glob('*.csv')
  files_list2 = [i for i in files_list if not i==output_fname]
  
  for file_item in files_list2:
      f = open(file_item)
      f.next() # skip the header
      for line in f:
           fout.write(line)
      f.close() 
  fout.close()
  
subject: Update merge_csv.py