private static ExternalLocation getExternalLocation(Symbol symbol) {
		if (symbol == null) {
			return null;
		}
		Program p = symbol.getProgram();
		return p.getExternalManager().getExternalLocation(symbol);
	}
Given a symbol for a specified program, get the corresponding symbol from the
specified otherProgram.
<br>
In the case of external locations this performs an exact match based upon symbol name, 
namespace and symbol type.

@param symbol symbol to look for
@param otherProgram other program
@return corresponding symbol for otherProgram or null if no such symbol exists.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/util/SimpleDiffUtility.java