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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 list_nodes(call=None):
    '''
    List VMs on this Azure account
    '''
    if call == 'action':
        raise SaltCloudSystemExit(
            'The list_nodes function must be called with -f or --function.'
        )

    ret = {}

    nodes = list_nodes_full()
    for node in nodes:
        ret[node] = {'name': node}
        for prop in ('id', 'image', 'size', 'state', 'private_ips', 'public_ips'):
            ret[node][prop] = nodes[node].get(prop)
    return ret