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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 cybox_valueset_fact_handler(self, enrichment, fact, attr_info, add_fact_kargs):
 """ Handler for dealing with 'value_set' values. Unfortunately, CybOX et al. sometimes use comma-separated value lists rather than an XML structure that can contain several values. This handler is called for elements concerning a value-set such as the following example:: <URIObj:Value condition="IsInSet" value_set="www.sample1.com/index.html, sample2.com/login.html, dev.sample3.com/index/kb.html" datatype="AnyURI"/> """


        value_list = attr_info['value_set'][fact['node_id']].split(",")
        value_list = map(lambda x: x.strip(), value_list)

        add_fact_kargs['values'] = value_list

        return True