Mastering Python for Finance - Second Edition

Declaring an abstract method for streaming prices

Add a stream_prices() abstract method that accepts a list of symbols in streaming prices using the following code:

@abstractmethod
def stream_prices(self, symbols=[]):
    """"
    Continuously stream prices from a broker.
    :param symbols: list of symbols recognized by your broker
    """
    raise NotImplementedError('Method is required!')

The inheriting child classes are expected to implement this method in streaming prices from your broker, otherwise a NotImplementedError exception message will be thrown.