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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 _parse_line(self, line_no, line):
 """Parse a line in a TileBus file Args: line_no (int):
 The line number for printing useful error messages line (string):
 The line that we are trying to parse """


        try:
            matched = statement.parseString(line)
        except ParseException as exc:
            raise DataError("Error parsing line in TileBus file", line_number=line_no, column=exc.col, contents=line)

        if 'symbol' in matched:
            self._parse_cmd(matched)
        elif 'filename' in matched:
            self._parse_include(matched)
        elif 'variable' in matched:
            self._parse_assignment(matched)
        elif 'configvar' in matched:
            self._parse_configvar(matched)