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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 _current_web_port(self):
 """ return just the port number for the web container, or None if not running """

        info = inspect_container(self._get_container_name('web'))
        if info is None:
            return None
        try:
            if not info['State']['Running']:
                return None
            return info['NetworkSettings']['Ports']['5000/tcp'][0]['HostPort']
        except TypeError:
            return None