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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 show_instance(name, call=None):
    '''
    Show the details from AzureARM concerning an instance
    '''
    if call != 'action':
        raise SaltCloudSystemExit(
            'The show_instance action must be called with -a or --action.'
        )
    try:
        node = list_nodes_full('function')[name]
    except KeyError:
        log.debug('Failed to get data for node \'%s\'', name)
        node = {}

    __utils__['cloud.cache_node'](node, __active_provider_name__, __opts__)

    return node