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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 upgrade_tools(name, reboot=False, call=None):
    '''
    To upgrade VMware Tools on a specified virtual machine.

    .. note::

        If the virtual machine is running Windows OS, use ``reboot=True``
        to reboot the virtual machine after VMware tools upgrade. Default
        is ``reboot=False``

    CLI Example:

    .. code-block:: bash

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

    vm_ref = salt.utils.vmware.get_mor_by_property(_get_si(), vim.VirtualMachine, name)

    return _upg_tools_helper(vm_ref, reboot)