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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 get_all_bandwidth_groups(self):
 """Get all managed bandwidth groups. return bandwidth_groups of type :class:`IBandwidthGroup` The array of managed bandwidth groups. """

        bandwidth_groups = self._call("getAllBandwidthGroups")
        bandwidth_groups = [IBandwidthGroup(a) for a in bandwidth_groups]
        return bandwidth_groups