'Deletes the specified instance group. The instances in the group
are not deleted. Note that instance group must not belong to a backend
service. Read  Deleting an instance group for more information.
Scopes needed - one of the following:
* https://www.googleapis.com/auth/cloud-platform
* https://www.googleapis.com/auth/compute
:param  instancegroup:  The name of the instance group to delete.
:type   instancegroup: :class:`GCEInstanceGroup`
:return:  Return True if successful.
:rtype: ``bool``'

def ex_destroy_instancegroup(self, instancegroup):

    request = ('/zones/%s/instanceGroups/%s' % (instancegroup.zone.name, instancegroup.name))
    request_data = {}
    self.connection.async_request(request, method='DELETE', data=request_data)
    return True
