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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 register_backend(self, name, backend):
 """ Register a new backend that will be called for each processed event. Note that backends are called in the order that they are registered. """

        if not hasattr(backend, 'send') or not callable(backend.send):
            raise ValueError('Backend %s does not have a callable "send" method.' % backend.__class__.__name__)
        else:
            self.backends[name] = backend