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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 retrieve_lead(self, *guid, **options):
 cur_guid = guid or '' params = {} for key in options: params[key] = options[key] """ Set guid to -1 as default for not finding a user """

        lead = {'guid' : '-1'}
        """ wrap lead call so that it doesn't error out when not finding a lead """
        try:
            lead = self._call('lead/%s' % cur_guid, params, **options)
        except:
            """ no lead here """
        return lead