code: def add_headers_to_df(fname_in, header_dict, fname_out=None):
      df = pd.read_csv(fname_in, header=None)
      df.rename(columns=header_dict, inplace=True)
      if fname_out is None:
          name, ext = os.path.splitext(fname_in)
          name += "-headers"
          fname_out = name + "." + ext
      df.to_csv(fname_out, index=False)  # save to new csv file
      return
  
imports: from .imports import *
  from subprocess import Popen
label_desc: Use image node_id 37 for calling a global function with example usage: add_headers_to_df(fname_in, header_dict, fname_out) without return types