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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 activate_nsxcontroller(self, **kwargs):
 """ Activate NSX Controller Args: name (str):
 nsxcontroller name callback (function):
 A function executed upon completion of the method. Returns: Return value of `callback`. Raises: None """

        name = kwargs.pop('name')
        name_args = dict(name=name)
        method_name = 'nsx_controller_activate'
        method_class = self._brocade_tunnels
        nsxcontroller_attr = getattr(method_class, method_name)
        config = nsxcontroller_attr(**name_args)
        output = self._callback(config)
        return output