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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 DEFINE_list(self, name, default, help, constant=False):
 """A helper for defining lists of strings options."""

    self.AddOption(
        type_info.List(
            name=name,
            default=default,
            description=help,
            validator=type_info.String()),
        constant=constant)