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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_volume(self):
 """Return the current volume level."""

        params = '<InstanceID>0</InstanceID><Channel>Master</Channel>'
        res = self.soap_request(URL_CONTROL_DMR, URN_RENDERING_CONTROL,
                                'GetVolume', params)
        root = ET.fromstring(res)
        el_volume = root.find('.//CurrentVolume')
        return int(el_volume.text)