計算ツールを作成したい

import tkinter
import math

root=tkinter.Tk()
root.title("偉大なる頭脳")
root.minsize(600,580)
root.option_add("*font",["MS ゴシック",20])

canvas=tkinter.Canvas(bg="#99ff22",width=700,height=480)
canvas.place(x=0,y=0)

def calc():
    global num_one
    global mark_in
    global num_two
    global answer
    num_one=int(one.get())
    mark_in=str(mark.get())
    num_two=int(two.get())
    if mark=='pi' or mark=='log2' or mark=='sqrt' or mark=='sin' or mark=='cos' or mark=='tan':
        ans()
        entry.delete(0,tkinter.END)
        entry.insert(0,answer)
    else:
        num_two=int(two.get())
        ans()
        entry.delete(0,tkinter.END)
        entry.insert(0,answer)

def ans():
    def sum():
        kotae=int(num_one+num_two)
        kotae["text"]=int(answer)

    def minus():
        answer=(num_one-num_two)
        answer["text"]=int(answer)

    def inc():
        answer=(num_one*num_two)
        answer["text"]=int(answer)

    def div():
        answer=(num_one/num_two)
        answer["text"]=int(answer)

    def div2():
        ans=(num_one//num_two)
        ans["text"]=str(ans)

    def joe():
        ans=(num_one**num_two)
        ans["text"]=str(ans)

    def extra():
        ans=(num_one%num_two)
        ans["text"]=str(ans)

    def circle():
        ans=(round(math.pi**num_one,2))
        ans["text"]=str(ans)

    def bottom():
        ans=((math.log2(num_one)))
        ans["text"]=str(ans)

    def sqrt():
        ans=((math.sqrt(num_one)))
        ans["text"]=str(ans)

    def sin():
        ans=(round(math.sin(math.radians(num_one))))
        ans["text"]=str(ans)

    def cos():
        ans=(round(math.cos(math.radians(num_one))))
        ans["text"]=str(ans)

    def tan():
        ans=(math.tan(math.radians(num_one)))
        ans["text"]=str(ans)

        if mark=='+':
            sum()
        elif mark=='-':
            minus()
        elif mark=='*':
            inc()
        elif mark=='/':
            div()
        elif mark=='//':
            div2()
        elif mark=='**':
            joe()
        elif mark=='%':
            extra()
        elif mark=='pi':
            circle()
        elif mark=='log2':
            bottom()
        elif mark=='sqrt':
            sqrt()
        elif mark=='sin':
            sin()
        elif mark=='cos':
            cos()
        elif mark=='tan':
            tan()

guide=tkinter.Label(text="1つ目の数字を入力してね",bg="#99ff22")
guide.place(x=80,y=50)

one=tkinter.Entry(width=12,bd=4)
one.place(x=400,y=50)

guide2=tkinter.Label(text="記号",bg="#99ff22")
guide2.place(x=80,y=150)

mark=tkinter.Entry(width=12,bd=4)
mark.place(x=400,y=150)

guide3=tkinter.Label(text="2つ目の数字を入力してね",bg="#99ff22")
guide3.place(x=80,y=250)

two=tkinter.Entry(width=12,bd=4)
two.place(x=400,y=250)

guide4=tkinter.Label(text="回答",bg="#99ff22")
guide4.place(x=80,y=350)

answer=tkinter.Entry(width=12,bd=4)
answer.pack(pady=10)
answer.place(x=400,y=350)

askbutton=tkinter.Button(master=root,text="計算する",command=calc)
askbutton.place(x=240,y=350)

entry=tkinter.Entry(master=root,width=12,bd=4)
entry.place(x=400,y=350)

root.mainloop()