<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def add_observer(self, observer, identify_observed=False):
 """Register an observer to observe me. Args: observer: The callable to register as an observer. identify_observed: If True, then the observer will get myself passed as an additional first argument whenever it is invoked. See ObserverFunction and ObserverBoundMethod to see how this works. Returns: True if the observer was added, False otherwise. The observing function or method will be called whenever I am called, and with the same arguments and keyword arguments. If a bound method or function has already been registered as an observer, trying to add it again does nothing. In other words, there is no way to sign up an observer to be called back multiple times. This was a conscious design choice which users are invited to complain about if there is a compelling use case where this is inconvenient. """


        # If the observer is a bound method,
        if hasattr(observer, "__self__"):
            result = self._add_bound_method(observer, identify_observed)
        # Otherwise, assume observer is a normal function.
        else:
            result = self._add_function(observer, identify_observed)
        return result