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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 raise_for_missing_default(self, line: str, position: int, name: str) -> None: """Raise an exeception if the name does not belong to the default namespace."""

        if not self.default_namespace:
            raise ValueError('Default namespace is not set')

        if name not in self.default_namespace:
            raise MissingDefaultNameWarning(self.get_line_number(), line, position, name)