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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(model, admin=None, category=None):
 """ Decorator to registering you Admin class. """

    def _model_admin_wrapper(admin_class):

        site.register(model, admin_class=admin_class)

        if category:
            site.register_block(model, category)

        return admin_class
    return _model_admin_wrapper