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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 guest_inspect_vnics(self, userid_list):
 """Get the vnics statistics of the guest virtual machines :param userid_list: a single userid string or a list of guest userids :returns: dictionary describing the vnics statistics of the vm in the form {'UID1': [{ 'vswitch_name': xx, 'nic_vdev': xx, 'nic_fr_rx': xx, 'nic_fr_tx': xx, 'nic_fr_rx_dsc': xx, 'nic_fr_tx_dsc': xx, 'nic_fr_rx_err': xx, 'nic_fr_tx_err': xx, 'nic_rx': xx, 'nic_tx': xx }, ], 'UID2': [{ 'vswitch_name': xx, 'nic_vdev': xx, 'nic_fr_rx': xx, 'nic_fr_tx': xx, 'nic_fr_rx_dsc': xx, 'nic_fr_tx_dsc': xx, 'nic_fr_rx_err': xx, 'nic_fr_tx_err': xx, 'nic_rx': xx, 'nic_tx': xx }, ] } for the guests that are shutdown or not exist, no data returned in the dictionary """

        if not isinstance(userid_list, list):
            userid_list = [userid_list]
        action = "get the vnics statistics of guest '%s'" % str(userid_list)
        with zvmutils.log_and_reraise_sdkbase_error(action):
            return self._monitor.inspect_vnics(userid_list)