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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 is_bound(method):
 """ Decorator that asserts the model instance is bound. Requires: 1. an ``id`` attribute 2. a ``url`` attribute 2. a manager set """

    @functools.wraps(method)
    def wrapper(self, *args, **kwargs):
        if not self._is_bound:
            raise ValueError("%r must be bound to call %s()" % (self, method.__name__))
        return method(self, *args, **kwargs)
    return wrapper