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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_appliance(self, id_or_uri, fields=''):
 """ Gets the particular Image Streamer resource based on its ID or URI. Args: id_or_uri: Can be either the Os Deployment Server ID or the URI fields: Specifies which fields should be returned in the result. Returns: dict: Image Streamer resource. """

        uri = self.URI + '/image-streamer-appliances/' + extract_id_from_uri(id_or_uri)
        if fields:
            uri += '?fields=' + fields

        return self._client.get(uri)