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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_campaign_name_list(self):
 """ Returns a list of all valid campaign names Returns: List of strings containing all valid campaign names """

        campaigns = self.find('campaigns', {})
        campaign_names = []
        for campaign in campaigns:
            if 'name' in campaign:
                campaign_names.append(campaign['name'])
        return campaign_names