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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_customizationspec_ref(si, customization_spec_name):
    '''
    Get a reference to a VMware customization spec for the purposes of customizing a clone

    si
        ServiceInstance for the vSphere or ESXi server (see get_service_instance)

    customization_spec_name
        Name of the customization spec

    '''
    customization_spec_name = si.content.customizationSpecManager.GetCustomizationSpec(name=customization_spec_name)
    return customization_spec_name