import datetime

class Dummy:
    def __init__(self, bias, baseline=1/3):
        """
        Initializes a Dummy instance with a given bias and baseline.
        
        Args:
        - bias (float): the bias value
        - baseline (float): the baseline value, default is 1/3
        """
        self.__bias = bias
        self.__baseline = baseline
        
    @property
    def bias(self):
        """
        Returns the bias value.
        """
        return self.__bias
    
    @property
    def baseline(self):
        """
        Returns the baseline value.
        """
        return self.__baseline
    
    @baseline.setter
    def baseline(self, value):
        """
        Sets the baseline value to a given value.
        
        Args:
        - value (float): the new baseline value
        """
        self.__baseline = value
    
    def calculate(self, multiplier):
        """
        Calculates the result of multiplier times baseline plus bias, rounded to 3 digits.
        
        Args:
        - multiplier (float): the multiplier value
        
        Returns:
        - result (float): the calculated result
        """
        result = round(multiplier * self.__baseline + self.__bias, 3)
        return result

    def get_current_datetime(self):
        """
        Returns the current time and date in the format hh:mm:ss dd/mm/yy using the `datetime` module.
        
        Returns:
        - formatted_date (string): time and date in the format hh:mm:ss dd/mm/yy
        """
        now = datetime.datetime.now()
        formatted_date = now.strftime("%H:%M:%S %d/%m/%Y")
        return formatted_date
