How to add custom sensor which is counting?

[Karabacak021]

Hey guys, I tried to add custom sensor but its not working.

There is my code:

class Smile(CustomDataSource):
    def __init__(self):
        self.current_value = 0
        self.last_val = [math.nan] * 10  # Initialize list with NaNs for the last 10 values
    def as_numeric(self) -> float:
        # Increment current_value and cycle from 0 to 9
        self.current_value = (self.current_value + 1) % 10
        
        # Store the value to the history list that will be used for line graph
        self.last_val.append(self.current_value)
        # Remove the oldest value from the history list
        self.last_val.pop(0)
        
        return self.current_value

    def as_string(self) -> str:
        # Return the current_value as a string
        return f'{self.current_value}'

    def last_values(self) -> List[float]:
        # Return the list of last numeric values
        return self.last_val

When I put into the Custom example theme, it just shows a static 1 number.

My main plan was to make a sensor which is a text one and cycle in this characters: 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,G,
But first I tried with numbers without success.

In the CustomDataExample theme I just replaced the ExampleCustomNumericData to Smile.

Thanks in advance :)