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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_app_version(self, app_config):
 """ Some plugins ship multiple applications and extensions. However all of them have the same version, because they are released together. That's why only-top level module is used to fetch version information. """


        base_name = app_config.__module__.split('.')[0]
        module = __import__(base_name)
        return getattr(module, '__version__', 'N/A')