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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 network_list(provider):
    '''
    List private networks

    CLI Example:

    .. code-block:: bash

        salt minionname cloud.network_list my-nova

    '''
    client = _get_client()
    return client.extra_action(action='network_list', provider=provider, names='names')