public CodeUnit getCodeUnitAt(Address address) {
		long addr = addrMap.getKey(address, false);
		// FIXME Trying to get Data to display for External.
		if (address.isExternalAddress()) {
			Symbol externalSymbol = program.getSymbolTable().getPrimarySymbol(address);
			if (externalSymbol == null) {
				return getUndefinedDataDB(address, addr);
			}
			ExternalLocation externalLocation =
				program.getExternalManager().getExternalLocation(externalSymbol);
			DataType dataType = externalLocation.getDataType();
			if (dataType == null || dataType == DataType.DEFAULT) {
				// For now dummy back an undefined.
				return getUndefinedDataDB(address, addr);
			}
			// Dummy back a Data for the data type.
			DataDB dataDB = new DataDB(this, null, addr, address, addr, dataType);
			return dataDB;
		}
		return getCodeUnitAt(addr);
	}
Returns the code unit whose min address equals the specified address.

@param address the min address of the code unit to return 
@return CodeUnit the code unit at the specified address, or null if a code unit does not 
exist
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/code/CodeManager.java