public final Function getFunctionBefore(Function function) {
		if (function == null) {
			return null;
		}
		Address start = function.getEntryPoint();
		return getFunctionBefore(start);
	}
Returns the function defined before the specified function in address order.
@param function the function
@return the function defined before the specified function
Ghidra/Features/Base/src/main/java/ghidra/program/flatapi/FlatProgramAPI.java