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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_content (self):
 """Return file content, or in case of directories a dummy HTML file with links to the files."""

        if self.is_directory():
            data = get_index_html(get_files(self.get_os_filename()))
            if isinstance(data, unicode):
                data = data.encode("iso8859-1", "ignore")
        else:
            data = super(FileUrl, self).read_content()
        return data