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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 set_string(self, option, value):
 """Set a string option. Args: option (str):
 name of option. value (str):
 value of the option. Raises: TypeError: Value must be a string. """

        if not isinstance(value, str):
            raise TypeError("%s must be a string" % option)

        self.options[option] = value