private Function getExistingFunction() {
		if (program == null || address == null) {
			return null;
		}
		return program.getFunctionManager().getFunctionAt(address);
	}
Returns the function at the context address
@return the function or null if program or address is null
Ghidra/Features/MicrosoftDemangler/src/main/java/ghidra/app/util/demangler/microsoft/MicrosoftMangledContext.java