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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_vcenter(self, **kwargs):
 """ Activate vCenter on the switch Args: name: (str) : Name of an established vCenter activate (bool) : Activates the vCenter if activate=True else deactivates it callback (function):
 A function executed upon completion of the method. Returns: Return value of `callback`. Raises: None """

        name = kwargs.pop('name')
        activate = kwargs.pop('activate', True)
        vcenter_args = dict(id=name)
        method_class = self._brocade_vswitch
        if activate:
            method_name = 'vcenter_activate'
            vcenter_attr = getattr(method_class, method_name)
            config = vcenter_attr(**vcenter_args)
            output = self._callback(config)
            print output
            return output
        else:
            pass