code: def get_expanded_schema(self, schema_name):
          
          if schema_name not in self.expanded_schemas:
              fn = self.get_schema_file(schema_name)
              schemas_folder = self.get_schemas_folder()
              base_uri = self.get_schema_path(schemas_folder)
  
              with open(fn) as f:
                  jsn_schema = jsonref.load(f, base_uri=base_uri)
  
                  # cache the schema for future use
                  self.expanded_schemas[schema_name] = jsn_schema
          else:
              jsn_schema = self.expanded_schemas[schema_name]
  
          return jsn_schema
docs: Return a schema file with all $ref properties expanded