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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_collections_for_image(self, image_id):
 """Get identifier of all collections that contain a given image. Parameters image_id : string Unique identifierof image object Returns ------- List(string) List of image collection identifier """

        result = []
        # Get all active collections that contain the image identifier
        for document in self.collection.find({'active' : True, 'images.identifier' : image_id}):
            result.append(str(document['_id']))
        return result