human
Solve the following python programming problem given the following code:
def build(self) : 
    f = FboFloatLayout () 
    b = Factory.Button (text = 'FBO', size_hint = (None, None)) 
    f.add_widget (b) 
    def anim_btn(* args) : 
        if (b.pos [0] == 0) : 
            Animation (x = (f.width - b.width)).start (b) 
else : 
            Animation (x = 0).start (b) 
b.bind (on_press = f) 
    return f 

    
    

    Fix the buggy line: b.bind (on_press = f)
assistant
#Here is Python program to fix the buggy line: b.

b.bind (on_press = def anim_btn()