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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_cron_line(self, line):
 """Parses crontab line and returns only starting time string Args: line: crontab line Returns: Time part of cron line """

        stripped = line.strip()

        if stripped and stripped.startswith('#') is False:
            rexres = self.rex.search(stripped)
            if rexres:
                return ' '.join(rexres.group(1).split())

        return None