def Update(self, signature):
    'Add the return types / exceptions of a signature to this instance.'
    if (signature.return_type not in self.return_types):
        self.return_types.append(signature.return_type)
    self.exceptions.extend((exception for exception in signature.exceptions if (exception not in self.exceptions)))
Add the return types / exceptions of a signature to this instance.
def Update(self, signature):
    
    if (signature.return_type not in self.return_types):
        self.return_types.append(signature.return_type)
    self.exceptions.extend((exception for exception in signature.exceptions if (exception not in self.exceptions)))