Ghidra_rename_fn.py

def rename_fn(name, offset):
    print("Offset " + hex(offset) + ", Name " + name)
    func = currentProgram.getFunctionManager().getFunctionAt(getAddress(offset))
    if func:
        func.setName(name, ghidra.program.model.symbol.SourceType.DEFAULT)
    else:
        print("Creating function...")
        cmd = ghidra.app.cmd.function.CreateFunctionCmd(getAddress(offset))
        if cmd.applyTo(currentProgram):
            print("Created function.")
			func = currentProgram.getFunctionManager().getFunctionAt(getAddress(offset))
			if func:
				func.setName(name, ghidra.program.model.symbol.SourceType.DEFAULT)
			else:
				print("FAILED to find the function we just created")
        else:
            print("FAILED to create function at " + hex(offset))