ProgramDB getProgram() {
		return program;
	}
{@return the default name for an external function or code symbol}
@param sym external label or function symbol
@throws IllegalArgumentException if external label or function symbol not specified or 
external symbol does not have an external program address.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/external/ExternalManagerDB.java