Hello, given the following code:

# Initializations
df_daily = pd.DataFrame()

# Set Start and End Dates with the following format "yyyy-mm-dd"
StartDate = "1969-12-31" #Set start date
EndDate = "2023-04-11"   #Set end date

Tickers = 'DPL#(MSJPAN$(MSPI),9),DPL#(MSJPAN$(MSRI),9),DPL#(MSEMUI$(MSPI),9),DPL#(MSEMUI$(MSRI),9),DPL#(MSEROP$(MSPI),9),DPL#(MSEROP$(MSRI),9'

# Set The Frequency Of The Data
Freq = 'D'

if Freq == 'D':    
        # Fetch daily data and add 1 period return               
        df_daily = ds.get_data(tickers=Tickers, start=StartDate, end=EndDate, freq=Freq)

with that ds.get_data function, how many tickers (reference prices) can I fetch at the same time with that instruction ? Is there a limit (because I had some limitation / errors when I inserted eg more than 20 tickers) ? Is the limit based on the total data points fetched per instruction or is just a limit per number of tickers ? Or there is a "string" length limit for the variable "Tickers" ?