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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 for this URL. Can be overridden in subclasses."""

        buf = StringIO()
        data = self.read_content_chunk()
        while data:
            if buf.tell() + len(data) > self.aggregate.config["maxfilesizedownload"]:
                raise LinkCheckerError(_("File size too large"))
            buf.write(data)
            data = self.read_content_chunk()
        return buf.getvalue()