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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_resource_types(self):
 """ Returns set of resource types of FileFields of all registered models. Needed by Cloudinary as resource type is needed to browse or delete specific files. """

        resource_types = set()
        for model in self.models():
            for field in self.model_file_fields(model):
                resource_type = field.storage.RESOURCE_TYPE
                resource_types.add(resource_type)
        return resource_types