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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 get_indicator(self, resource):
 """Return the modification time and size of a `Resource`."""

        path = resource.real_path
        # on dos, mtime does not change for a folder when files are added
        if os.name != 'posix' and os.path.isdir(path):
            return (os.path.getmtime(path),
                    len(os.listdir(path)),
                    os.path.getsize(path))
        return (os.path.getmtime(path),
                os.path.getsize(path))