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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 _tail_file(self, file, interval):
 """Tails a file"""

        file.seek(0,2)
        while True:
            where = file.tell()
            line = file.readline()
            if not line:
                time.sleep(interval)
                file.seek(where)
            else:
                yield line