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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 terminate(name, call=None):
    '''
    To do an immediate power off of a VM using its name. A ``SIGKILL``
    is issued to the vmx process of the VM

    CLI Example:

    .. code-block:: bash

        salt-cloud -a terminate vmname
    '''
    if call != 'action':
        raise SaltCloudSystemExit(
            'The terminate action must be called with '
            '-a or --action.'
        )

    vm_properties = [
        "name",
        "summary.runtime.powerState"
    ]

    vm_list = salt.utils.vmware.get_mors_with_properties(_get_si(), vim.VirtualMachine, vm_properties)

    for vm in vm_list:
        if vm["name"] == name:
            if vm["summary.runtime.powerState"] == "poweredOff":
                ret = 'already powered off'
                log.info('VM %s %s', name, ret)
                return ret
            try:
                log.info('Terminating VM %s', name)
                vm["object"].Terminate()
            except Exception as exc:
                log.error(
                    'Error while terminating VM %s: %s',
                    name, exc,
                    # Show the traceback if the debug logging level is enabled
                    exc_info_on_loglevel=logging.DEBUG
                )
                return 'failed to terminate'

    return 'terminated'