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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 was_modified_since_last_sync(self):
 """Return True if this resource was modified since last sync. None is returned if we don't know (because of missing meta data). """

        info = self.get_sync_info()
        if not info:
            return None
        if self.size != info["s"]:
            return True
        if self.mtime > info["m"]:
            return True
        return False