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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 data and data size for this URL. Can be overridden in subclasses."""

        maxbytes = self.aggregate.config["maxfilesizedownload"]
        buf = StringIO()
        for data in self.url_connection.iter_content(chunk_size=self.ReadChunkBytes):
            if buf.tell() + len(data) > maxbytes:
                raise LinkCheckerError(_("File size too large"))
            buf.write(data)
        return buf.getvalue()