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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 fetch(self, vault_client):
 """Populate internal representation of remote Vault resource contents"""

        result = self.read(vault_client)
        if result:
            if isinstance(result, dict) and 'data' in result:
                self.existing = result['data']
            else:
                self.existing = result
        else:
            self.existing = None