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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 get_boolean(self, section, name, default=None):
 """Retrieve a configuration setting as boolean. :param section: Tuple with section name and optional subsection namee :param name: Name of the setting, including section and possible subsection. :return: Contents of the setting :raise KeyError: if the value is not set """

        try:
            value = self.get(section, name)
        except KeyError:
            return default
        if value.lower() == "true":
            return True
        elif value.lower() == "false":
            return False
        raise ValueError("not a valid boolean string: %r" % value)