I'm currently building a program in Pycharm and want to use the Eikon API to retreive 2 fields: CF_Last and TR.priceclose (SDate=-1M). However, when i give up ISIN codes as instrument names, i get an error, while RICs do seem to work. Is there any way to do this based on ISIN? import tkinter as tk from tkinter import filedialog import pandas as pd import eikon as ek # API Key ek.set_app_key('') # Define the list of instrument codes and fields to retrieve instrument_codes = ['BE0974293251', 'NL0010273215'] fields = ['CF_LAST', 'TR.PriceClose(SDate=-1M)'] # Retrieve the data using the Eikon API data, err = ek.get_data(instrument_codes, fields) # Check for errors if err: raise ValueError(err) # Print the resulting DataFrame print(data)