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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 stop(vm_):
    '''
    Hard power down the virtual machine, this is equivalent to pulling the
    power

    CLI Example:

    .. code-block:: bash

        salt '*' virt.stop <vm name>
    '''
    with _get_xapi_session() as xapi:
        vm_uuid = _get_label_uuid(xapi, 'VM', vm_)
        if vm_uuid is False:
            return False
        try:
            xapi.VM.hard_shutdown(vm_uuid)
            return True
        except Exception:
            return False