python tkinter写的计算器

还有小问题，可以初步学习tkinter，可以参考做很多小程序。

#coding =utf-8
'''
    name:
    function:
    author:ww
    time:2019/1/11 8:40
    software:PyCharm
   
'''

import tkinter,time,decimal,math,string


root=tkinter.Tk()
root.title('计算器')
root.resizable(0,0)
global cuncu, vartext, result, fuhao
result = fuhao = None
vartext = tkinter.StringVar()
cuncu = []

class anjianzhi:
    global cuncu, vartext, result, fuhao
    def __init__(self,anjian):
        self.anjian = anjian
    def jia(self):
        cuncu.append(self.anjian)
        vartext.set( ''.join(cuncu))
    def tui(self):
        cuncu.pop()
        vartext.set(''.join(cuncu))
    def clear(self):
        cuncu.clear()
        vartext.set('')
        result = None
        fuhao = None
    def zhengfu(self):
        if cuncu[0]:
            if cuncu[0] == '-':
                cuncu[0] = '+'
            elif cuncu[0] == '+':
                cuncu[0] = '-'
            else:
                cuncu.insert(0, '-')
        vartext.set(''.join(cuncu))
    def xiaoshudian(self):
        if cuncu.count('.') >= 1:
            pass
        else:
            if cuncu == [] :
                cuncu.append('0')
            cuncu.append('.')
            vartext.set(''.join(cuncu))
    def yunshuan(self):
        global cuncu, vartext, result, fuhao
        if vartext.get() == '':
            pass
        else:
            get1 = decimal.Decimal(vartext.get())
            if self.anjian in ('1/x','sqrt'):
                if self.anjian == '1/x':
                    result = 1/get1
                elif self.anjian == 'sqrt':
                    result = math.sqrt(get1)
            elif  self.anjian in ('+','-','*','/','='):
                if fuhao is not None:
                    get1 = decimal.Decimal(result)
                    get2 = decimal.Decimal(vartext.get())
                    if fuhao == '+':
                        result = get1 + get2
                    elif fuhao == '-':
                        result = get1 - get2
                    elif fuhao == '*':
                        result = get1 * get2
                    elif fuhao == '/':
                        result = get1 / get2
                else:
                    result = get1
                if self.anjian == '=':
                    fuhao = None
                else:
                    fuhao = self.anjian
            print(fuhao)
            print(result)
            vartext.set(str(result))
            cuncu.clear()

def copy1():
    # tkinter.Misc().clipboard_clear()
    tkinter.Misc().clipboard_append(string(vartext.get()))

def buju(root):
    global cuncu, vartext, result, fuhao
    entry1 = tkinter.Label(root, width=30, height=2, bg='white', anchor='se', textvariable=vartext)
    entry1.grid(row=0, columnspan=5)
    buttonMC=tkinter.Button(root,text='MC',width=5)
    buttonMR=tkinter.Button(root,text='MR',width=5)
    buttonMS=tkinter.Button(root,text='MS',width=5)
    buttonM1=tkinter.Button(root,text='M+',width=5)
    buttonM2=tkinter.Button(root,text='M-',width=5)
    buttonMC.grid(row=1,column=0)
    buttonMR.grid(row=1,column=1)
    buttonMS.grid(row=1,column=2)
    buttonM1.grid(row=1,column=3)
    buttonM2.grid(row=1,column=4)


    buttonJ=tkinter.Button(root,text='←',width=5,command=anjianzhi('c').tui)
    buttonCE=tkinter.Button(root,text='CE',width=5)
    buttonC=tkinter.Button(root,text=' C ',width=5,command=anjianzhi('c').clear)
    button12=tkinter.Button(root,text='±',width=5,command=anjianzhi('c').zhengfu)
    buttonD=tkinter.Button(root,text='√',width=5,command=anjianzhi('sqrt').yunshuan)
    buttonJ.grid(row=2,column=0)
    buttonCE.grid(row=2,column=1)
    buttonC.grid(row=2,column=2)
    button12.grid(row=2,column=3)
    buttonD.grid(row=2,column=4)

    button7=tkinter.Button(root,text=' 7 ',width=5,command=anjianzhi('7').jia)
    button8=tkinter.Button(root,text=' 8 ',width=5,command=anjianzhi('8').jia)
    button9=tkinter.Button(root,text=' 9 ',width=5,command=anjianzhi('9').jia)
    buttonc=tkinter.Button(root, text=' / ',width=5,command=anjianzhi('/').yunshuan)
    buttonf= tkinter.Button(root, text=' % ',width=5)
    button7.grid(row=3,column=0)
    button8.grid(row=3,column=1)
    button9.grid(row=3,column=2)
    buttonc.grid(row=3,column=3)
    buttonf.grid(row=3,column=4)

    button4=tkinter.Button(root,text=' 4 ',width=5,command=anjianzhi('4').jia)
    button5=tkinter.Button(root,text=' 5 ',width=5,command=anjianzhi('5').jia)
    button6=tkinter.Button(root,text=' 6 ',width=5,command=anjianzhi('6').jia)
    buttonx=tkinter.Button(root,text=' * ',width=5,command=anjianzhi('*').yunshuan)
    buttonfs=tkinter.Button(root,text='1/x',width=5,command=anjianzhi('1/x').yunshuan)
    button4.grid(row=4,column=0)
    button5.grid(row=4,column=1)
    button6.grid(row=4,column=2)
    buttonx.grid(row=4,column=3)
    buttonfs.grid(row=4,column=4)

    button1 = tkinter.Button(root, text=' 1 ',width=5,command=anjianzhi('1').jia)
    button2 = tkinter.Button(root, text=' 2 ',width=5,command=anjianzhi('2').jia)
    button3 = tkinter.Button(root, text=' 3 ',width=5,command=anjianzhi('3').jia)
    button_= tkinter.Button(root, text=' - ',width=5,command=anjianzhi('-').yunshuan)
    buttondy= tkinter.Button(root, text=' \n = \n ',width=5,command=anjianzhi('=').yunshuan)
    button1.grid(row=5, column=0)
    button2.grid(row=5, column=1)
    button3.grid(row=5, column=2)
    button_.grid(row=5, column=3)
    buttondy.grid(row=5, column=4,rowspan=2)

    button0=tkinter.Button(root,text='   0   ',width=11,command=anjianzhi('0').jia)
    buttonjh = tkinter.Button(root,text=' . ',width=5,command=anjianzhi('c').xiaoshudian)
    buttonjia=tkinter.Button(root,text=' + ',width=5,command=anjianzhi('+').yunshuan)
    button0.grid(row=6,column=0,columnspan=2)
    buttonjh.grid(row=6,column=2)
    buttonjia.grid(row=6,column=3)
def caidan(root):

    menu=tkinter.Menu(root)
    submenu1=tkinter.Menu(menu,tearoff=0)
    menu.add_cascade(label='查看',menu=submenu1)
    submenu2 = tkinter.Menu(menu, tearoff=0)
    submenu2.add_command(label='复制')
    submenu2.add_command(label='粘贴')
    menu.add_cascade(label='编辑',menu=submenu2)
    submenu = tkinter.Menu(menu, tearoff=0)
    submenu.add_command(label='查看帮助')
    submenu.add_separator()
    submenu.add_command(label='关于计算机')
    menu.add_cascade(label='帮助',menu=submenu)
    root.config(menu=menu)


buju(root)
caidan(root)
root.mainloop()