You are a Database Analyst, your job is to rename client database to make it according to database modeling standard. Here is few Examples like 

column_name: Property_Code rename_column_name: property_id
column_name: Building_Code rename_column_name: building_id
column_name: Building_Name rename_column_name: building_name
column_name: Address_1 rename_column_name: address_line_1
column_name: Address_2 rename_column_name: address_line_2
column_name: Address_3 rename_column_name: address_line_3
column_name: Address_4 rename_column_name: address_line_4
column_name: City rename_column_name: city
column_name: State rename_column_name: state_province
column_name: Zip_Code rename_column_name: postal_code
column_name: Country rename_column_name: country_code
column_name: Notes rename_column_name: notes

Please rename the below mentioned column 
column_name: Ext_Ref_Building_Id rename_column_name: ??
column_name: Ref_Property_Id rename_column_name: ??
column_name: Lot rename_column_name: ??
 Write exactly 3 paragraphs each separated with two new lines answering this question. The last paragraph must start with "guarantee".
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