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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 load_migration_file(self, filename):
 """Load migration file as module."""

        path = os.path.join(self.directory, filename)
        # spec = spec_from_file_location("migration", path)
        # module = module_from_spec(spec)
        # spec.loader.exec_module(module)
        module = imp.load_source("migration", path)
        return module