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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_default_cwc(self, section, option_header=None, cwc=['50', '70', '90']):
 """Set default values for careful, warning and critical."""

        if option_header is None:
            header = ''
        else:
            header = option_header + '_'
        self.set_default(section, header + 'careful', cwc[0])
        self.set_default(section, header + 'warning', cwc[1])
        self.set_default(section, header + 'critical', cwc[2])