Replace Data Source of Each Query with Generic Data Source

Hi 

I am selecting from view in my projects 

I want change Data source for all queries to generic Data Source when I will move from dev to prod

1. I created Blank Query 

DS_AG

usinng Advice editor I specified Source as 

let
Source = Sql.Database("DESKTOP-DJZ12\AGCMS", "PowerBIDX")
in
Source

In my Existing  Query01  Source  

let
Source = Sql.Database("DESKTOP-DJZ12\AGCMS", "PowerBIDX", [Query="SELECT [DATAAREAID] as LegalEntity,#(lf) [NAME] as LegalEntityName#(lf)FROM [V_CompaniesLegalEntities]"])
in
Source

I   want to replace "DESKTOP-DJZ12\AGCMS", "PowerBIDX"  with DS_AG

something  like 

let
Source = Sql.Database("DS_AG", [Query="SELECT [DATAAREAID] as LegalEntity,#(lf) [NAME] as LegalEntityName#(lf)FROM [V_CompaniesLegalEntities]"])
in
Source

please help with syntax  or  show example