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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 read_string_option (self, section, option, allowempty=False):
 """Read a string option."""

        if self.has_option(section, option):
            value = self.get(section, option)
            if not allowempty and not value:
                raise LinkCheckerError(_("invalid empty value for %s: %s\n") % (option, value))
            self.config[option] = value