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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 distance_between(self, string, start, end):
 """Returns number of lines between start and end"""

        count = 0
        started = False

        for line in string.split("\n"):

            if self.scan_line(line, start) and not started:
                started = True

            if self.scan_line(line, end):
                return count

            if started:
                count += 1

        return count