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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add_signal(self, signal):

 """Adds "input" signal to connected signals.
 Internally connects the signal to a control slot."""

        self.__signals.append(signal)
        if self.__connected:
            # Connects signal if the current state is "connected"
            self.__connect_signal(signal)