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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 _init_net_specs(conf):
 """ Given a configuration specification, initializes all the net definitions in it so they can be used comfortably Args: conf (dict):
 Configuration specification Returns: dict: the adapted new conf """

        for net_name, net_spec in conf.get('nets', {}).items():
            net_spec['name'] = net_name
            net_spec['mapping'] = {}
            net_spec.setdefault('type', 'nat')

        return conf