def has_option_tag(self, section, option, tag):
        """
        Convenience function accessing has_option_tags() for a single tag: see
        documentation for that function.
        NB calling has_option_tags() directly is preferred for simplicity.

        Parameters
        -----------
        self : ConfigParser object
            The ConfigParser object (automatically passed when this is appended
            to the ConfigParser class)
        section : string
            The section of the ConfigParser object to read
        option : string
            The ConfigParser option to look for
        tag : string
            The name of the subsection to look in, if not found in [section]

        Returns
        --------
        Boolean
            Is the option in the section or [section-tag]
        """
        return self.has_option_tags(section, option, [tag])
Convenience function accessing has_option_tags() for a single tag: see
        documentation for that function.
        NB calling has_option_tags() directly is preferred for simplicity.

        Parameters
        -----------
        self : ConfigParser object
            The ConfigParser object (automatically passed when this is appended
            to the ConfigParser class)
        section : string
            The section of the ConfigParser object to read
        option : string
            The ConfigParser option to look for
        tag : string
            The name of the subsection to look in, if not found in [section]

        Returns
        --------
        Boolean
            Is the option in the section or [section-tag]