init

fibonacci.py

@@ -0,0 +1,38 @@
+from tkinter import *
+
+x = 1
+y = 1
+z = 0
+
+class App:
+    def __init__(self, master):
+        frame = Frame(master)
+        frame.pack()
+
+        self.textVar = StringVar()
+
+        # Lambda Version
+        # self.button = Button(
+        #     frame, textvariable=self.textVar, command=lambda: self.textVar.set(fibonacci())
+        # )
+        # self.button.pack()
+        
+        # tkinter Version, using separate functions
+        self.button = Button(
+            frame, textvariable=self.textVar, command=self.update
+        )
+        self.button.pack()
+
+    def update(self):
+        self.textVar.set(str(fibonacci()))
+        
+def fibonacci():
+    global x, y, z
+    z = x
+    x = x + y
+    y = z
+    return x
+
+root = Tk()
+app = App(root)
+root.mainloop()