Lghtning - How to take sObject as a return type into the component?

How to take sObject as a return type into the component?

In the below example we are passing sObject data i.e. acc the helper from there to controller fom there to component. 
In the component when we initialized the attribute we didn't sepecify default as default="{'sObjectType':'Account'}"
because we are getting the acc data from Apex and we are sure that we are getting Account data only hence we didn't initialized. 

<aura:handler name="init" value="{!this}" action="{!c.callMe}" /> -- Same as constructer. In this example we have only shown one record 
if we want to display multiple records either we need to go for data table / iterator. 

Component
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<aura:component controller="Example_Four">
    <aura:attribute name="acc" type="Account" />
    <aura:handler name="init" value="{!this}" action="{!c.callMe}" />
    <lightning:card iconName="standard:account">
    	<aura:set attribute="title">
        	<h1> Account</h1>
            <h1>{!v.acc.Name}</h1>
        </aura:set>
        
        <aura:set attribute="actions">
            <lightning:Button label="Save" />
            <lightning:Button label="Cancel" />
        </aura:set>
        <lightning:layout>
        	<lightning:layoutItem size="2" padding="around-small" >
                Name : <br/>{!v.acc.Name}
            </lightning:layoutItem>
            <lightning:layoutItem size="2" padding="around-small" >
                Phone :<br/> {!v.acc.Phone}
            </lightning:layoutItem>
            <lightning:layoutItem size="2" padding="around-small" >
                Industry :<br/> {!v.acc.Industry}
            </lightning:layoutItem>
            <lightning:layoutItem size="2" padding="around-small" >
                Rating :<br/> {!v.acc.Rating}
            </lightning:layoutItem>
        </lightning:layout>
    </lightning:card>
</aura:component>
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Controller
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({
	callMe : function(component, event, helper) {
		helper.callHelper(component);
	}
})
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Helper
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({
	callHelper : function(component) {
		var action=component.get("c.invokeAcc");
        action.setCallback(this,function(response){
            var state=response.getState();
            if(state==='SUCCESS'){
                var acc=response.getReturnValue();
                console.log(acc);
                component.set("v.acc",acc);
            }
        });
        $A.enqueueAction(action);
	}
})
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Apex Class
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public class Example_Four {
	@AuraEnabled 
    public static Account invokeAcc(){
        Account acc =[select id,Name,Phone,Industry,Rating from Account limit 1];
        return acc;
    }
}
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