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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 permissions(self, perms):
 """ A decorator that sets a list of permissions for a function. :param perms: The list of permission instances or classes. :return: A function """


        if not isinstance(perms, (list, tuple)):
            perms = [perms]

        instances = []

        for perm in perms:
            if isclass(perm):
                instances.append(perm())
            else:
                instances.append(perm)

        def decorator(func):
            func.permissions = instances
            return func
        return decorator