code: def complete_profile(f, credentials, session_token_written, mfa_serial_written):
      
      session_token = credentials['SessionToken'] if 'SessionToken' in credentials else None
      mfa_serial = credentials['SerialNumber'] if 'SerialNumber' in credentials else None
      if session_token and not session_token_written:
          f.write('aws_session_token = %s\n' % session_token)
      if mfa_serial and not mfa_serial_written:
          f.write('aws_mfa_serial = %s\n' % mfa_serial)
docs: Append session token and mfa serial if needed
  
      :param f:
      :param credentials:
      :param session_token_written:
      :param mfa_serial_written:
      :return: