Здравейте, 

Опитвам се да създам Sumator от глава пътва на Programming basics - Python Но ми дава грешка. Някой би ли ми погледнал кода и би ли ми показал къде ми е грешката?

import tkinter as tk

class Application(tk.Frame):
    def _init_(self, master=None):
        super()._init_(master)

        self.pack()


app = Application()
app.master.title("Sumator")
app.master.minsize(width=100, height=50)

app.mainloop()


def _init_(self, master=None):
    super()._init_(master)

    self.pack()
    self.create_widgets()


def create_widgets(self):

    #    create widgets
    self.firstNumberEntry = tk.Entry()
    self.plusSign = tk.Label(text="+")
    self.secondNumberEntry = tk.Entry()
    self.equalSign = tk.Label(text="=")
    self.resultLabel = tk.Label(text="Result...",
                                bg="green", fg="white")
    self.calculateButton = tk.Button(text="Calculate")

    self.firstNumberEntry.pack(side="left")
    self.plusSign.pack(side="left")
    self.seconNumberEntry.pack(side="left")
    self.equalSign.pack(side="left")
    self.resultLabel.pack(side="left")
    self.calculateButton.pack(side="left")

tk.Button(text="Calculate", command=self.calculate)

def calculate(self):
    first_value = float(self.firstNumberentry.get())
    second_value = float(self.secondNumberentry.get())
    result = first_value + second_value
    elf.resultLabel.gonfig(text=str(result),
                            bg="green", fg="white")

def calculate(self):
    try:
        first_value = float(self.firstNumberentry.get())
        secon_value = floqt(self.secondNumberentry.get())
        result = first_value + secon_value
        self.resutLabel.config(text=str(result),
                                bg="green", fg="white")
    except valueError:
        self.resultLablel.config(text=str(result),
                                bg="red", fg="black")

Поздрави,

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