I'm facing a problem in lookup field.

For Example:  On "Potentials" module ,there is a standard lookup field named "Account Name" and it has a standard deluge name "ACCOUNTID" through which we access record values for particular selected record.

e.g.

potential_info = zoho.crm.getRecordById("Potentials",input.CS_Opportunity_End_User_ID);

if(potential_info.size() > 0)

{

if(potential_info.get("ACCOUNTID") != null)

{

input.CS_End_User_ID = potential_info.get("ACCOUNTID").toLong();

input.CS_End_User = potential_info.get("Account Name");

}

} 

Here we are checking if ACCOUNTID is not equal, then we populate "Account Name" in "End User " Custom field.

But, I am trying to do same for a custom lookup field to "Accounts" module and I am unable to find key(like ACCOUNTID).

where does key or this unique exist in zoho crm?

Could somebody please help me to find this key for a custom lookup field?

Any help would be appreciated.